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  • 51.
    Munjulury, Raghu
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Berry, Patrick
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Borhani Coca, D.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Pares Prat, A.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Krus, Petter
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Analytical weight estimation of landing gear designs2017Inngår i: Proceedings of the Institution of Mechanical Engineers. Part G, Journal of Aerospace Engineering, ISSN 0954-4100, E-ISSN 2041-3025, Vol. 231, nr 12, s. 2214-2227Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Landing gear weight calculations can be carried out using statistical or analytical methods. Statistical methods were used in the past and offered quick group weights. However, they are not capable of computing accurately the weight of landing gears, which have special geometries and performance. In this work, landing gear weight is computed using analytical methods based on parametric 3D models. The procedure established by Kraus and Wille is applied as a baseline so as to create a procedure capable of dealing with landing gear weight calculations. This method is designed to be as flexible as possible, giving the user the freedom to modify many options and parameters and integrate landing gear design into Robust Aircraft Parametric Interactive Design.

  • 52.
    Munjulury, Raghu Chaitanya
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Knowledge-Based Integrated Aircraft Design: An Applied Approach from Design to Concept Demonstration2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The design and development of new aircraft are becoming increasingly expensive and timeconsuming. To assist the design process in reducing the development cost, time, and late design changes, the conceptual design needs enhancement using new tools and methods. Integration of several disciplines in the conceptual design as one entity enables to keep the design process intact at every step and obtain a high understanding of the aircraft concepts at early stages.

    This thesis presents a Knowledge-Based Engineering (KBE) approach and integration of several disciplines in a holistic approach for use in aircraft conceptual design. KBE allows the reuse of obtained aircrafts’ data, information, and knowledge to gain more awareness and a better understanding of the concept under consideration at early stages of design. For this purpose, Knowledge-Based (KB) methodologies are investigated for enhanced geometrical representation and enable variable fidelity tools and Multidisciplinary Design Optimization (MDO). The geometry parameterization techniques are qualitative approaches that produce quantitative results in terms of both robustness and flexibility of the design parameterization. The information/parameters from all tools/disciplines and the design intent of the generated concepts are saved and shared via a central database.

    The integrated framework facilitates multi-fidelity analysis, combining low-fidelity models with high-fidelity models for a quick estimation, enabling a rapid analysis and enhancing the time for a MDO process. The geometry is further propagated to other disciplines [Computational Fluid Dynamics (CFD), Finite Element Analysis (FEA)] for analysis. This is possible with an automated streamlined process (for CFD, FEM, system simulation) to analyze and increase knowledge early in the design process. Several processes were studied to streamline the geometry for CFD. Two working practices, one for parametric geometry and another for KB geometry are presented for automatic mesh generation.

    It is observed that analytical methods provide quicker weight estimation of the design and when coupled with KBE provide a better understanding. Integration of 1-D and 3-D models offers the best of both models: faster simulation, and superior geometrical representation. To validate both the framework and concepts generated from the tools, they are implemented in academia in several courses at Linköping University and in industry

    Delarbeid
    1. A knowledge-based integrated aircraft conceptual design framework
    Åpne denne publikasjonen i ny fane eller vindu >>A knowledge-based integrated aircraft conceptual design framework
    2016 (engelsk)Inngår i: CEAS Aeronautical Journal, ISSN 1869-5582, 1869-5590, Vol. 7, nr 1, s. 95-105Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    "The conceptual design is the early stage of aircraft design process where results are needed fast, both analytically and visually so that the design can be analyzed and eventually improved in the initial phases. Although there is no necessity for a CAD model from the very beginning of the design process, it can be an added advantage to have the model to get the impression and appearance. Furthermore, this means that a seamless transition into preliminary design is achieved since the CAD model can guardedly be made more detailed. For this purpose, knowledge-based aircraft conceptual design applications Tango (Matlab) and RAPID (CATIA) are being developed at Linköping University. Based on a parametric data definition in XML, this approach allows for a full 3D CAD integration. The one-database approach, also explored by many research organizations, enables the flexible and efficient integration of the different multidisciplinary processes during the whole conceptual design phase. This paper describes the knowledge-based design automated methodology of RAPID, data processing between RAPID and Tango and its application in the courses ‘‘Aircraft conceptual design’’ and ‘‘Aircraft project course’’ at Linköping University. A multifaceted user interface is developed to assist the whole design process."

    sted, utgiver, år, opplag, sider
    Springer, 2016
    Emneord
    Aircraft conceptual design, Knowledge based, XML database
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-126689 (URN)10.1007/s13272-015-0174-z (DOI)
    Prosjekter
    NFFP5/NFFP6
    Tilgjengelig fra: 2016-04-01 Laget: 2016-04-01 Sist oppdatert: 2018-02-07
    2. Knowledge-based design for future combat aircraft concepts
    Åpne denne publikasjonen i ny fane eller vindu >>Knowledge-based design for future combat aircraft concepts
    Vise andre…
    2014 (engelsk)Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    A new fighter aircraft will most likely be acollaborative project. In this study conceptualknowledge-based design is demonstrated, usingmodels of comparable fidelity for sizing, geometrydesign, aerodynamic analysis and system simulationfor aircraft conceptual design. A newgeneration fighter is likely to involve advancedcontrol concept where an assessment of feasibilitythrough simulation is needed already atthe conceptual stage. This co-design leads to adeeper understanding of the trade-offs involved.In this paper a study for a future combat aircraftis made. Conceptual knowledge-based design isdemonstrated by optimizing for a design mission,including a super-cruise segment.

    sted, utgiver, år, opplag, sider
    St. Peterberg: , 2014
    Emneord
    Conceptual design, Aircraft design, Engine design, Knowledge-based
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-114902 (URN)
    Konferanse
    29th Congress of the International Council of the Aeronautical Sciences, St. Petersburg, Russia
    Prosjekter
    NFFP5/NFFP6
    Tilgjengelig fra: 2015-03-05 Laget: 2015-03-05 Sist oppdatert: 2017-05-30bibliografisk kontrollert
    3. Knowledge-based future combat aircraft optimization
    Åpne denne publikasjonen i ny fane eller vindu >>Knowledge-based future combat aircraft optimization
    2016 (engelsk)Inngår i: 30th Congress of the International Council of the AeronauticalSciences (ICAS 2016), Bonn: International Council of Aeronautical Sciences (ICAS) , 2016, Vol. 1, s. 273-280Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    Future combat aircraft inherently conceal all the components internally essentially for stealth reasons. The geometry is optimized for subsonic and supersonic flight area distribution and the components and payload to be fitted inside the aircraft. The basic requirements to accomplish are fuel consumption, mission profile, and military performance. Analytical methods comprise of a quick aerodynamic and structural optimization. The result obtained is then compared with multi-fidelity aero-structural analysis

    sted, utgiver, år, opplag, sider
    Bonn: International Council of Aeronautical Sciences (ICAS), 2016
    Emneord
    Knowledge Based, Combat aircraft, Conceptual Design, Optimization
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-137644 (URN)978-1-5108-3455-2 (ISBN)
    Konferanse
    30th Congress of the International Council of the Aeronautical Sciences, Daejeon, South Korea, 25-30 September 2016.
    Prosjekter
    NFFP5/NFFP6
    Tilgjengelig fra: 2017-05-23 Laget: 2017-05-23 Sist oppdatert: 2017-06-02bibliografisk kontrollert
    4. A comprehensive computational multidisciplinary design optimization approach for a tidal power plant turbine
    Åpne denne publikasjonen i ny fane eller vindu >>A comprehensive computational multidisciplinary design optimization approach for a tidal power plant turbine
    Vise andre…
    2017 (engelsk)Inngår i: Advances in Mechanical Engineering, ISSN 1687-8132, E-ISSN 1687-8140, Vol. 9, nr 3, s. 1-13, artikkel-id 1687814017695174Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Multidisciplinary design optimization has become a powerful technique to facilitate continuous improvement of complex and multidisciplinary products. Parametric modeling is an essential part with tremendous impact on the flexibility and robustness of multidisciplinary design optimization. This article investigates the effect of relational and non-relational parameterization techniques on the robustness and flexibility of the conceptual design of a multidisciplinary product. Bench marking between relational and non-relational parameterization and their effect on flexibility and robustness indicate that the relational parameterization is an efficient method in the multidisciplinary design optimization process. The inherent properties of the method contribute to an efficient parametric modeling with improved communication between different disciplines. This enhances the performance of the multidisciplinary design optimization process and allows a more flexible and robust design. The considered disciplines are computer-aided design, computational fluid dynamics, finite element analysis, and dynamic simulation. A high-fidelity geometry created in a computer-aided design environment is computer-aided design centric approach and later used in computational fluid dynamics, finite element analysis for a better understanding of the product as it leads to precise outcomes. The proposed approach is implemented for the conceptual design of a novel product, a tidal power plant developed by Minesto AB using a multidisciplinary design optimization process.

    sted, utgiver, år, opplag, sider
    London: Sage Publications, 2017
    Emneord
    Parametric modeling, conceptual design, computer-aided design, computational fluid dynamics, finite element analysis, dynamic simulation, multidisciplinary design optimization
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-137645 (URN)10.1177/1687814017695174 (DOI)000400394500001 ()2-s2.0-85018345706 (Scopus ID)
    Prosjekter
    NFFP5/NFFP6
    Tilgjengelig fra: 2017-05-23 Laget: 2017-05-23 Sist oppdatert: 2017-06-14bibliografisk kontrollert
  • 53.
    Munjulury, Raghu Chaitanya
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Berry, Patrick
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Melin, Tomas
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Amadori, Kristian
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Krus, Petter
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Knowledge-based Integrated Wing Automation and Optimization for Conceptual Design2015Inngår i: 16th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference16th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference, 2015Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Contemporary aircraft design and development incurs high costs and consumes a lot of time for research and implementation. To minimize the development cost, an improvement of the conceptual design phase is desirable. A framework to support the initial design space exploration and conceptual design phase is presently being developed at Linköping University. In the aircraft design, the geometry carries a critical, discriminating role since it stores a significant part of the information and the data needed for most investigations. Methodology for design automation of a wing with a detailed description such that the geometry is effectively propagated for further analysis is presented in this paper. Initial weight estimation of the wing is performed by combining the weight penalty method with a sophisticated CAD model. This wing model is used for airfoil shape optimization and later for structural optimization. A methodology for automatic meshing of the geometry for CFD and FEM when the surfaces increase or decrease during the design automation is proposed. The framework combining automation capability with shape and structural optimization will enhance the early design phases of aircraft conceptual design.

  • 54.
    Munjulury, Raghu Chaitanya
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Martins Abdalla, Alvaro
    USP, São Carlos, Brazil.
    Staack, Ingo
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Krus, Petter
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Knowledge-based future combat aircraft optimization2016Inngår i: 30th Congress of the International Council of the AeronauticalSciences (ICAS 2016), Bonn: International Council of Aeronautical Sciences (ICAS) , 2016, Vol. 1, s. 273-280Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Future combat aircraft inherently conceal all the components internally essentially for stealth reasons. The geometry is optimized for subsonic and supersonic flight area distribution and the components and payload to be fitted inside the aircraft. The basic requirements to accomplish are fuel consumption, mission profile, and military performance. Analytical methods comprise of a quick aerodynamic and structural optimization. The result obtained is then compared with multi-fidelity aero-structural analysis

  • 55.
    Munjulury, Raghu Chaitanya
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Nadali Najafabadi, Hossein
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanisk värmeteori och strömningslära. Linköpings universitet, Tekniska fakulteten.
    Safavi, Edris
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Ölvander, Johan
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Petter, Krus
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Karlsson, Matts
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanisk värmeteori och strömningslära. Linköpings universitet, Tekniska fakulteten.
    A comprehensive computational multidisciplinary design optimization approach for a tidal power plant turbine2017Inngår i: Advances in Mechanical Engineering, ISSN 1687-8132, E-ISSN 1687-8140, Vol. 9, nr 3, s. 1-13, artikkel-id 1687814017695174Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Multidisciplinary design optimization has become a powerful technique to facilitate continuous improvement of complex and multidisciplinary products. Parametric modeling is an essential part with tremendous impact on the flexibility and robustness of multidisciplinary design optimization. This article investigates the effect of relational and non-relational parameterization techniques on the robustness and flexibility of the conceptual design of a multidisciplinary product. Bench marking between relational and non-relational parameterization and their effect on flexibility and robustness indicate that the relational parameterization is an efficient method in the multidisciplinary design optimization process. The inherent properties of the method contribute to an efficient parametric modeling with improved communication between different disciplines. This enhances the performance of the multidisciplinary design optimization process and allows a more flexible and robust design. The considered disciplines are computer-aided design, computational fluid dynamics, finite element analysis, and dynamic simulation. A high-fidelity geometry created in a computer-aided design environment is computer-aided design centric approach and later used in computational fluid dynamics, finite element analysis for a better understanding of the product as it leads to precise outcomes. The proposed approach is implemented for the conceptual design of a novel product, a tidal power plant developed by Minesto AB using a multidisciplinary design optimization process.

  • 56.
    Munjulury, Raghu Chaitanya
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Staack, Ingo
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Abdalla, Alvaro Martins
    The University of São Paulo (USP), Brazil.
    Melin, Tomas
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Jouannet, Christopher
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Krus, Petter
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Knowledge-based design for future combat aircraft concepts2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A new fighter aircraft will most likely be acollaborative project. In this study conceptualknowledge-based design is demonstrated, usingmodels of comparable fidelity for sizing, geometrydesign, aerodynamic analysis and system simulationfor aircraft conceptual design. A newgeneration fighter is likely to involve advancedcontrol concept where an assessment of feasibilitythrough simulation is needed already atthe conceptual stage. This co-design leads to adeeper understanding of the trade-offs involved.In this paper a study for a future combat aircraftis made. Conceptual knowledge-based design isdemonstrated by optimizing for a design mission,including a super-cruise segment.

  • 57.
    Munjulury, Raghu Chaitanya
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Staack, Ingo
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Berry, Patrick
    Saab Aeronautics, Linköping.
    Krus, Petter
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    A knowledge-based integrated aircraft conceptual design framework2016Inngår i: CEAS Aeronautical Journal, ISSN 1869-5582, 1869-5590, Vol. 7, nr 1, s. 95-105Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    "The conceptual design is the early stage of aircraft design process where results are needed fast, both analytically and visually so that the design can be analyzed and eventually improved in the initial phases. Although there is no necessity for a CAD model from the very beginning of the design process, it can be an added advantage to have the model to get the impression and appearance. Furthermore, this means that a seamless transition into preliminary design is achieved since the CAD model can guardedly be made more detailed. For this purpose, knowledge-based aircraft conceptual design applications Tango (Matlab) and RAPID (CATIA) are being developed at Linköping University. Based on a parametric data definition in XML, this approach allows for a full 3D CAD integration. The one-database approach, also explored by many research organizations, enables the flexible and efficient integration of the different multidisciplinary processes during the whole conceptual design phase. This paper describes the knowledge-based design automated methodology of RAPID, data processing between RAPID and Tango and its application in the courses ‘‘Aircraft conceptual design’’ and ‘‘Aircraft project course’’ at Linköping University. A multifaceted user interface is developed to assist the whole design process."

  • 58.
    Munjulury, Raghu
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Staack, Ingo
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Filosofiska fakulteten.
    Sabate Lopez, Adrian
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling. Linköpings universitet, Tekniska fakulteten.
    Krus, Petter
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Knowledge-based aircraft fuel system integration2018Inngår i: AIRCRAFT ENGINEERING AND AEROSPACE TECHNOLOGY, ISSN 1748-8842, Vol. 90, nr 7, s. 1128-1135Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose This paper aims to present a knowledge-based fuel system, implementation and application, oriented towards its use in aircraft conceptual design. Design/methodology/approach Methodology and software tools oriented to knowledge-based engineering applications (MOKA) is used as a foundation for the implementation and integration of fuel systems. Findings Including fuel systems earlier in the design process creates an opportunity to optimize it and obtain better solutions by allocating suitable locations in an aircraft, thereby reflecting on the centre of gravity of the aircraft. Research limitations/implications All geometries are symbolic, representing a space allocation inside the aircraft for the fuel system. A realistic representation of the real components could be realized in detail design. Practical implications Fuel weight is a significant part of take-off weight and decisive in aircraft sizing and range estimations. The three-dimensional geometry provides a better estimation of the volume that is available to allocate the necessary entities. It also provides fast measures for weight and balance, fuel capacity, relative tank positions and a first estimation of piping length. Originality/value Fuel systems appear early in the design process, as they are involved in several first estimations. By using a knowledge-based engineering approach, several alternatives can be visualized and estimated in the conceptual design process. Furthermore, using the weights and centre of gravity at different angles of pitch and roll of each fuel tank, the aircraft could be optimized for handling qualities by using automatically generated system simulation models.

  • 59.
    Munjulury, Venkata Raghu Chaitanya
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Berry, Patrick
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Krus, Petter
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    RAPID – Robust Aircraft Parametric Interactive Design: A Knowledge Based Aircraft Conceptual Design Tool2013Inngår i: Proceedings of the 4th CEAS Conference in Linköping 2013: 4:th CEAS conference, 2013 / [ed] Tomas Melin, Petter Krus, Emil Vinterhav and Knut Övrebo, Linköping, 2013, s. 255-262Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Conceptual design is the early stage of theaircraft design process where results areneeded faster both analytically and visually sothat the design can be modified or changed atthe earliest stages. Although there is nonecessity for a CAD model from the verybeginning of the design process it can be anadded advantage to have the model, to get theimpression and appearance.Tango and RAPID are knowledge basedaircraft conceptual design applications beingdeveloped in Matlab and CATIA respectively.The user can work in parallel with bothprograms and exchange the data between themvia XML. This paper describes the knowledgebased design automated methodology of RAPIDand its application in the courses “Aircraftconceptual design” and “Aircraft projectcourse” at Linköping University. A multifaceteduser interface is developed to assist in the wholedesign processes.

  • 60.
    Munjulury, Venkata Raghu Chaitanya
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Staack, Ingo
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Krus, Petter
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Integrated Aircraft Design Network2013Inngår i: CEAS 2013 The International Conference of the European Aerospace Societies: 4:th CEAS conference, 2013 / [ed] Tomas Melin, Petter Krus, Emil Vinterhav, Knut Övrebo, Linköping, 2013, s. 263-269Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper describes the XML basedmultidisciplinary tool integration in aconceptual aircraft design framework,developed by the Division of Fluid andMechatronic Systems (FluMeS), LinköpingUniversity. Based on a parametric datadefinition in XML, this approach allows for afull 3D CAD integration. The one-databaseapproach, also conducted by many researchorganizations, enables the flexible and efficientintegration of the different multidisciplinaryprocesses during the whole conceptual designphase. This central database approach with adetailed explanation of the developed geometrydescription and the data processing, focusing onthe CAD integration is presented. Applicationexamples of the framework are presentedshowing the data build up and data handling.

  • 61.
    Nangunoori, Chetan Kumar
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Kumar Bhaskar, Ravichandra Kumar
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Parametric Ram Air Channel Model for Flow Optimization2012Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Ram air channel or NACA channel is used to direct the ambient air for various purposes in an aircraft, such as pressurizing the cabin or as a coolant to heat exchangers and even more other applications like a cooling of the coolant. It is designed; such that it supplies the required amount of ambient air for various operations as mentioned, even aero-dynamical features should be taken into consideration while designing.

    In past, the developed prototypes are to be designed first and then experimented to optimize the design which gives accurate predictions and makes easy to understand the phenomenon occurring. These methods can lead to lot of waste in resources and time, in order to avoid these, some new mathematical methods have been implemented before finalizing the prototype which might save resources, time and minimize the possibility of having wrong outcomes. Some additional steps are included during calculation stage prior to the prototype stage; they are the computer aided simulations. These simulations can be as accurate as real time simulations and can bring closer to accuracy rate which is a needed prior to prototype stage.

    The aim is to design a tool chain for a Ram air channel which in turn is used to optimize the flow, then supplied to heat exchangers for cooling the hot refrigerant from the avionics systems. The requirements of the heat exchanger are decided on the applications it is used and the range of temperature to be cooled.

    In this study work, firstly estimate the size of the heat exchanger for the required performance, followed by the geometry of Ram air channel designing in CAD application so that it maintains the required amount of mass flow rate for the performance of heat exchanger. Finally these both components are implemented in simulation loop to iterate the designs of NACA channel in order to get the final model to optimize the flow for a heat exchanger.

     

  • 62.
    Nilsson, Sara
    et al.
    SAAB Aerostructures, Linköping.
    Jensen, Jonas
    Volvo Construction Equipment.
    Björkman, Mats
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell Produktion. Linköpings universitet, Tekniska fakulteten.
    Sundin, Erik
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell Produktion. Linköpings universitet, Tekniska fakulteten.
    11 Rules of Design for Manufacturing CFRP Components2018Inngår i: So You Want to Design Aircraft: Manufacturing with Composites / [ed] Jean Broge, SAE International , 2018, First, s. 29-42Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Carbon-fiber-reinforced plastic (CFRP) is one of the most commonly used materials in the aerospace industry today. CFRP in pre-impregnated form is an anisotropic material whose properties can be controlled to a high level by the designer. Sometimes, these properties make the material hard to predict with regards to how the geometry affects manufacturing aspects. This chapter describes 11 design rules that describe geometrical design choices and deals with manufacturability problems that are connected to them, why they are connected, and how they can be minimized or avoided. Examples of design choices dealt with in the rules include double curvature shapes, assembly of uncured CFRP components, and access for nondestructive testing.

  • 63.
    Nyman, Lina
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system.
    Estimation of Aerodynamic Parameters in Real-Time: Implementation and Comparison of a Sequential Frequency Domain Method and a Batch Method2016Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The flight testing and evaluation of collected data must be efficient during intensive flight-test programs such as the ones conducted during development of new aircraft. The aim of this thesis has thus been to produce a first version of an aerodynamic derivative estimation program that is to be used during real-time flight tests. The program is to give a first estimate of the aerodynamic derivatives as well as check the quality of the data collected and thus serve as a decision support during tests.

    The work that has been performed includes processing of data in order to use it in computations, comparing a batch and a sequential estimation method using real-time data and programming a user interface. All computations and programming has been done in Matlab.

    The estimation methods that have been compared are both built on transforming data to the frequency domain using a Chirp z-transform and then estimating the aerodynamic derivatives using complex least squares with instrumental variables.The sequential frequency domain method performs estimates at a given interval while the batch method performs one estimation at the end of the maneuver. Both methods compared in this thesis produce equal results. The continuous updates of the sequential method was however found to be better suited for a real-time application than the single estimation of the batch method.

    The telemetric data received from the aircraft must be synchronized to a common frequency of 60 Hz. Missing samples of the data stream must be linearly interpolated and different units of measured parameters must be corrected in order to be able to perform these estimations in the real-time test environment.

  • 64.
    Olsen, Rickard
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell Produktion. Linköpings universitet, Tekniska högskolan.
    Johansen, Kerstin
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska högskolan.
    Assembly cell concept for human and robot in cooperation2013Inngår i: 22nd International Conference on Production Research: Challenges for sustainable operations, 2013Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Today’s aerospace assembly is a huge manual task according to strictly controlled instructions, where differentoperators are responsible for different areas. This harmonizes with the overall lean approach, but the assemblyis very time-consuming and some tasks are not ergonomically friendly, such as assembly tasks inside a wingbox. Here, it could be possible to increase automation with the aim to facilitate a shorter assembly time andergonomically improved workplace. This paper will present different assembly cell concepts utilizing differentsafety strategies to achieve human-robot cooperation in an aerospace industry assembly line. These conceptswill be discussed in relation to a case in the aerospace industry. The paper concludes with suggestions forthree conceptual human-robot cooperation layouts. These are based on previous research in the areas ofsafety and human-robot cooperation, in combination with observations from an aerospace assembly line.

  • 65.
    Papageorgiou, Athanasios
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Development of a Multidisciplinary Design Optimization Framework Applied on UAV Design2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The present thesis deals with the topic of Multidisciplinary Design Optimization (MDO) and in particular with the development of a framework for Unmanned Aerial Vehicle (UAV) design. The orientation of the research and the overall outlook of the case-study have been based on Saab’s proposal regarding the application of MDO in complex products and are in compliance with the guidelines of the Innovative Multidisciplinary Product Optimization (IMPOz) project initiative. For this initial stage of the project, five principle engineering disciplines related to aircraft design were considered and those were namely the geometric design, the aerodynamics, the antenna analysis, the Radar Cross Section (RCS) signature, and the mission simulation. The aforementioned disciplines were expressed within the framework by developing computational models which were further based on a relevant set of engineering tools. In the present case-study, the primary focus was on using the indicated engineering tools which are available to both Linköping University and Saab but also to investigate viable and more efficient alternatives. A simple optimization strategy was implemented as a guide for the integration of the models and the core framework configuration was evaluated by using the Design Of Experiments (DOE) method. Finally, the use of metamodels as a tool that can increase the computational efficiency of the framework was analyzed and a preliminary optimization of the product was performed as an example of the framework’s capabilities.

  • 66.
    Papageorgiou, Athanasios
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Amadori, Kristian
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Jouannet, Christopher
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Ölvander, Johan
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Multidisciplinary Optimization of Unmanned Aircraft in a System of Systems Context2018Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    This paper explores the use of Multidisciplinary Design Optimization (MDO) in the development of Unmanned Aerial Vehicles (UAVs) when the requirements include a collaboration in a System of Systems (SoS) environment. In this work, the framework considers models that can capture the mission, stealth, and surveillance performance of each aircraft, while at the same time, a dedicated simulation module assesses the total cooperation effect on a given operational scenario. The resulting mixed continuous and integer variable problem is decomposed with a multi-level architecture, and in particular, it is treated as a fleet allocation problem that includes a nested optimization routine for sizing a “yet-to-be-designed” aircraft. Overall, the models and the framework are evaluated through a series of optimization runs, and the obtained Pareto front is compared with the results from a traditional aircraft mission planning method in order to illustrate the benefits of this SoS approach in the design of UAVs.

  • 67.
    Papageorgiou, Athanasios
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Tarkian, Mehdi
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Amadori, Kristian
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Andersson (Ölvander), Johan
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Multidisciplinary Optimization of Unmanned Aircraft Considering Radar Signature, Sensors, and Trajectory Constraints2018Inngår i: Journal of Aircraft, ISSN 0021-8669, E-ISSN 1533-3868, Vol. 55, nr 4, s. 1629-1640Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper presents a multidisciplinary design optimization framework applied to the development of unmanned aerial vehicles with a focus on radar signature and sensor performance requirements while simultaneously considering the flight trajectory. The primary emphasis herein is on the integration and development of analysis models for the calculation of the radar cross section and sensor detection probability, whereas traditional aeronautical disciplines such as aerodynamics and mission simulation are also taken into account in order to ensure a flyable concept. Furthermore, this work explores the effect of implementing trajectory constraints as a supplementary input to the multidisciplinary design optimization process and presents a method that enables the optimization of the aircraft under a three-dimensional flight scenario. To cope with the additional computational cost of the high-fidelity radar cross section and sensor calculations, the use of metamodels is also investigated and an efficient development methodology that can provide high-accuracy approximations for this particular problem is proposed. Overall, the operation and performance of the framework are evaluated against five surveillance scenarios, and the obtained results show that the implementation of trajectory constraints in the optimization has the potential to yield better designs by 12–25% when compared to the more “traditional” problem formulations.

  • 68.
    Papageorgiou, Athanasios
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Ölvander, Johan
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    A Data Management and Visualization Tool for Integrating Optimization Results in Product Development2018Inngår i: DS 91: Proceedings of NordDesign 2018, Linköping, Sweden, 14th - 17th August 2018: DESIGN IN THE ERA OF DIGITALIZATION / [ed] Ekströmer, Philip; Schütte, Simon and Ölvander, Johan, 2018Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    This paper presents a data management and visualization tool that was developed in parallel with a Multidisciplinary Design Optimization (MDO) framework in order to enable a more effective use of the obtained results within the Product Development Process (PDP). To this date, the main problem is that the majority of MDO case studies conclude by suggesting a small number of optimal configurations, which do not really hold any meaningful value for the decision makers since they represent only a narrow area of the design space. In this light, the proposed tool aims to provide designers with new possibilities in respect to post-processing of large data sets, and subsequently, to allow the non-technical teams to be engaged and benefit from the use of MDO in the company practices. As an example, an Unmanned Aerial Vehicle (UAV) configurator developed by using the Graphical User Interface (GUI) of MATLAB is herein presented, and it is shown that a tool for handling the results can be the logical next step towards integrating MDO in the manufacturing industry. Overall, this work aims to demonstrate the benefits of the present visualization and management tool as a complementary addition to an existing optimization framework, and also to determine if this approach can be the right strategy towards improving the MDO method for an eventual use in the PDP of complex pro-ducts like UAVs.

  • 69.
    Papageorgiou, Athanasios
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Ölvander, Johan
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Amadori, Kristian
    Saab Aeronautics, Sweden.
    Development of a Multidisciplinary Design Optimization Framework Applied on UAV Design by Considering Models for Mission, Surveillance, and Stealth Performance2017Inngår i: 18th AIAA/ISSMO Multidisciplinary Analysis and Optimization Conference, 2017Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    This paper presents a Multidisciplinary Design Optimization (MDO) framework that is intended to be employed in the early design stages of Unmanned Aerial Vehicles (UAVs) when the primary focus is on the tradeoffs between the mission, stealth, and surveillance performance requirements. The proposed MDO framework takes into account the aircraft’s geometry, the aerodynamics, the trim, the stability, and the simulation of the mission, but it also includes two additional models for computing the Radar Cross Section (RCS) and the sensor performance. A multi-level solution architecture is implemented in order to tackle the increased complexity of the problem, and it is shown that this type of decomposition can be a more efficient optimization approach compared to the traditional single-level formulation. The operation of the framework is evaluated through single objective optimizations by using the weighted sum method, while it is also investigated whether or not metamodels can be a viable alternative to the computationally expensive RCS and sensor analysis models. Overall, the results show that the mission, stealth, and surveillance performance are conflicting objectives, and therefore, their concurrent consideration in an optimization framework can help increase the available knowledge early on in the design of UAV applications.

  • 70.
    Parras Blázquez, Pedro Santiago
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanisk värmeteori och strömningslära.
    CFD Analysis of Pressure Instabilities in Stator-Rotor Disc Cavity Systems2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
  • 71.
    Parés Prat, Andreu
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Borhani Coca, Dario
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Munjulury, Raghu Chaitanya
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Berry, Patrick
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Analytical weight estimation of unconventional landing gear designs2015Inngår i: Proceedings of the Institution of MechanicalEngineers, Part G: : Journal of Aerospace Engineering, 2015, , s. 10Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Landing gear weight calculations can be carried out using statistical or analytical methods. Statistical methods were used in the past and offered quick group weights, however, they are not capable of computing with accuracy the weight of unconventional landing gears which have special geometries and performances. In this work, landing gear weight is computed using analytical methods. The procedure established by Kraus and Wille is acquired as a baseline so as to create a program able to deal with landing gear weight calculations. This software has been designed to be as much flexible as possible, giving the user the freedom to modify many options and parameters.

  • 72.
    Pehrson, Mats
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell Produktion.
    Sehlin, Daniel
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Industriell Produktion.
    Integrering av robotar hos Saab Aerostructures: En förstudie med huvudfokus på kollaborativa robotar och möjliga tillämpningar för dessa i produktionen av flygplansstrukturer2016Independent thesis Basic level (university diploma), 10,5 poäng / 16 hpOppgave
    Abstract [sv]

    Denna rapport behandlar automationsmöjligheter inom Saab. Arbetet bedrevs på den civila sidan av Saab i Linköping, mer känd som Saab Aerostructures, som ett examensarbete på kandidatnivå. Flygplansindustrin har i dagsläget en relativt låg grad av automatiserad tillverkning. Detta till följd av de många olika komplicerade moment som utförs samt av den relativt låga produktionstakten. Syftet med det här examensarbetet var att undersöka möjligheterna till att utöka graden av automatiserad tillverkning inom Saab Aerostructures produktion.

    För att undersöka detta spenderades tid i produktionen för att studera hur arbetet utförs. Med hjälp av undersökningen och samtal med personer inom produktionen togs ett antal tillämpningar fram på uppgifter som kan tänkas automatiseras med en robot. Eftersom Saab har begränsad erfarenhet inom det här området är den här rapporten mer av en förstudie för att sätta bollen i rullning och få företaget att börja integrera nya lösningar för att få en mer effektiv och automatiserad tillverkning av flygplansstrukturer.  

    Arbetet resulterade i att två stycken olika förslag på automationslösningar ges. De två förslagen skiljer sig en hel del åt vad gäller både uppgift och lösning. Det ena föreslås använda sig av en robot som går att arbeta med sida vid sida, utan fysiska avgränsningar i form av stängsel. Den andra lösningen använder en traditionell industrirobot i en vanlig miljö med en skyddsbur. Lösningen med den traditionella industriroboten ser mest lovande ut eftersom arbetet som roboten kommer utföra resulterar i att cirka 40 operatörstimmar per vecka frigörs. Payback-tiden för den investeringen är ungefär 4 år, vilket Saab anser vara överkomligt. Denna lösning kombinerar tre uppgifter: fräsning, tätning och målning som alla utförs på en lastdörr.

  • 73.
    Pettersson, Karl
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten. Volvo Construction Equipment.
    Larsson, L. Viktor
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Larsson, K. Viktor
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Krus, Petter
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Simulation Aided Design and Testing of Hydromechanical Transmissions2014Inngår i: The 9th JFPS International Symposium on Fluid Power, Matsue, 2014, 2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper demonstrates the use of high-speed simulation in transmission conceptual design and presents a transmission test bed for hardware-in-the-loop simulations of hydromechanical transmission concepts. Complex transmissions, such as multiple-mode hydromechanical transmissions and hydraulic hybrid transmissions, present new difficulties and costs in the development process. There is today a greater demand for more efficient product development and more work has shifted towards simulation. The Hopsan simulation package allows robust, high-speed simulations suitable for both offline and hardware-in-the-loop simulation. New simulation models for hydromechanical transmissions are developed and used to simulate a known two-mode transmission concept. The same concept is also tested in hardware-in-the-loop simulations in the proposed transmission test bed. Results show good agreement with the hardware tests and highlight the proficiency of the simulation tools.

  • 74.
    Poudel, Sabin
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system.
    Modelling of a Generic Aircraft Environmental Control System in Modelica2019Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This thesis documents the modelling of generic Environmental Control System(ECS) of an aircraft in Modelica by utilizing components from free version of theTTECCS (Technical Thermodynamic Environmental Control and Cooling Systems) library. In doing so, components used for developing ECS from the TTECCS library are mathematically verified with theoretical formula in MATLAB. Selected components are investigated with valid input data to initialize the simulation and verify its behaviors with corresponding available data. Hereinafter, the object-oriented modelling method is used to integrate ECS components to develop a functional system. The main function of ECS is to regulate the pressure and temperature inside the cabin to accepted physiology flight safetylevels. Different types of ECS architecture are presented in this document. An ECS developed here is based on the bootstrap system and consists only one cooling unit comprised with the source, pipes, two heat exchanger, compressor, turbine, temper-ature control valve, pressure control valve, and sinks. Dry air(Ideal gas) is used as a medium in the system. Temperature drop along each component corresponds to available A320 cruise flight data in order to calculate the top level parameter and to initialize the components, subsequently an ECS system. Several systematized methods for Object-oriented modelling and system design were studied and steps are extracted accordingly that suits to initiate the procedurefor this project, which is also presented. Time domain simulation is performed inModelica and Dymola. A simplified control system is built to regulate the system, therefore restrained it as a future work to develop real in-flight condition control system of an ECS.Top level parameters were selected within valid customized ranges for developing a performance map of the components. After generating the map, optimal data from the map were taken to initialize final ECS. The simulation results of the final model is then compared to A320 flight data which is comparable in behavior; this was expected. Above all, simulation environment Modelica and free version of TTECCS library components are reliable to develop ECS in order to investigate ECS components behavior and predict cabin conditions before developing a prototype.

  • 75.
    Prameswari, Carry
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. -.
    Simulation Model Development of a Subscale Fighter Demonstrator: Aerodynamic Database Generation and Propulsion Modeling2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The main objective of this thesis was to improve the simulation model of a subscale fighter demonstratorthat had been developed previously. In order to give a reliable result, the simulation model should be modeled correctly and employ accurate input. To fulfill this objective two approaches was performed, the first was by providing the aerodynamic derivatives database in order to be implemented  in the simulation model, and the second process is to improve the propulsion module of the  simulation model. The aerodynamic database was generated by several VLM and panel  method software, namely Tornado, VSPAero and XFLR5, which uses subscale fighter  demonstrator called Generic Future Fighter  (GFF) as the aircraft model. The results from  different methods and software were then compared first before it was implemented to the  simulation model. The second process includesenhancing the propulsion model and implementation of the aerodynamic database.The propulsion model enhancement covers the improvement of thrust modeling and development of fuel consumption model. Additionally, the aerodynamic database implementation was executed by connecting the  external sets of the database into the simulation  model automatically. The verification process  was performed by comparing the result of the simulation model against recorded flight data, also by comparing the improved and the  previous simulation model result to see the effect of improvement that was carried out. Using the improved model of engine thrust and fuel consumption model, the propulsion module can produce a reliable outcome of forces and   moments computation. Moreover, theimplementation of the aerodynamic database  also gives a significant improvement in the simulation model result.

  • 76.
    Rosén, Malin
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Boström, Andreas
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Conceptual Design of a Variable Air Inlet, JAS 39 Gripen2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The JAS 39 Gripen currently has a static air inlet designed for cooling the engine bay. This inlet has been developed over the years and has consisted of several different solutions. In this master’s thesis an investigation of past and current designs has been conducted in order to develop new concepts with a variable solution. Since the static inlet is designed for a worst case scenario, long duration of flight at low altitudes and high atmospheric temperatures, the cooling produced is not always needed and instead causes an unnecessary amount of drag. Developing concepts with variable solutions would alter the caption area depending on flight case and thereby decrease drag accordingly.

    Both aerodynamic and airworthiness properties are important to consider when developing concepts of an air inlet. Initially a concept generation was conducted in order to create possible concepts for implementation. 14 concepts were generated, evaluated and analyzed resulting in two concepts chosen based on their superior aerodynamic and airworthiness properties. Screening was done with both a Pugh matrix as well as a scoring matrix.

    One of the selected concepts has a similar design to the current scoop inlet, but with a variable solution. The second is a variable NACA duct design. An alternative solution briefly discussed was that of a static design, with different caption areas, attached to the service door depending on location of operation and flight conditions but is only theoretical at this point.

    The advantage of implementing the NACA concept would be the decrease in drag since it is a flush inlet. The weight and radar cross section (RCS) are both considered to be low when compared to the scoop concept. Shortcomings of the NACA concept would include the uncertainty in performance concerning cooling and producing sufficient mass flow, as well as the uncertainty in case of bird strike. The scoop concept is similar to the current design and therefore is a verified design with satisfactory bird strike properties as well as having a high probability of producing sufficient mass flow. When compared to the NACA duct it has disadvantages concerning drag, weight, RCS and foreign object damage.

  • 77.
    Sabaté López, Adrián
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Munjulury, Raghu Chaitanya
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Parametric Modeling of Aircraft Fuel Systems integration in RAPID2015Rapport (Annet vitenskapelig)
    Abstract [en]

    This work presents knowledge-based parametricdefinition of aircraft fuel systems, oriented to itsuse in conceptual design and integrated into theRAPID design tool. Fuel systems appear earlyin the design process as they are involved in severalfirst estimations. For instance, fuel weight isa significant part of take-off weight and decisivein aircraft sizing and range estimations. Therefore,including fuel systems earlier in the designprocess creates an opportunity to optimize it andobtain better solutions.

  • 78.
    Safavi, Edris
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska högskolan.
    Model Based Multidisciplinary Aircraft Systems Design and Optimization for Conceptual Phase2013Konferansepaper (Annet vitenskapelig)
  • 79.
    Safavi, Edris
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska högskolan.
    Gopinath, Varun
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska högskolan.
    Ölvander, Johan
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska högskolan.
    Gavel, Hampus
    SAAB AB, Sweden.
    A Collaborative Tool for Conceptual Aircraft Systems Design2012Inngår i: Guidance, Navigation, and Control and Co-located Conferences: AIAA Modeling and Simulation Technologies Conference / [ed] The American Institute of Aeronautics and Astronautics, Reston, VA, USA: American Institute of Aeronautics and Astronautics, 2012, s. 1-10Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Advances in recent years has brought forth many feasible technologies which oer signif-icant design advantages over the traditional aircraft vehicle ight systems. These advanceshave brought about a need for the aircraft conceptual engineers to evaluate these newtechnologies so as to realize a realistic and optimized architecture which fulls all criti-cal disciplinary requirements. To evaluate these systems, it is necessary to use models ofcomplexity which are a degree higher than what is being used today. Quick developmentand evaluation of these models can be a hard task for an engineer to achieve consideringthe multidisciplinary nature of the systems. A collaborative eort in model developmentbetween various department is needed if the conceptual design is to be completed withinthe time frame. To facilitate a collaborative conceptual design a research project was for-malized at Linkoping university, which has led to the development of a tool named CAVE(Conceptual Aircraft Vehicle Engineering) which can be used to evaluate the architectureof aircraft systems. In this paper, CAVE as a conceptual design tool will be presented.

  • 80.
    Safavi, Edris
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska högskolan.
    Gopinath, Varun
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska högskolan.
    Ölvander, Johan
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska högskolan.
    Gavel, Hampus
    SAAB AB, Sweden.
    Conceptual Optimization of Aircraft Actuator Systems2012Inngår i: Proceedings of the International Conference on recent advances in aerospace actuation systems and components, Toulouse, France: Institut national des sciences appliquées , 2012, s. 201-Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    The aim of this research project is to identify a preliminary architecture of a flight control actuation system concept for energy optimized aircraft system architecture with the focus on more electrical aircraft. At Linköping University a design framework is being developed to assist in the evaluation of aircraft flight system at a conceptual level using dynamic models which has led to the development of a tool named CAVE.

    In this paper the use of the framework to approach the problem of finding a suitable flight actuator system for a number of flight control surfaces distributed over the aircraft with different boundary conditions (maximum torque and flap deflection) is presented. Dynamic models for three of the most commonly used actuation technologies have been developed in Dymola and each system has been optimized with mass and energy consumption as the objectives.

  • 81.
    Safavi, Edris
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Tarkian, Mehdi
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Ölvander, Johan
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska fakulteten.
    Nadali Najafabadi, Hossein
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanisk värmeteori och strömningslära. Linköpings universitet, Tekniska fakulteten.
    Munjulury, Raghu Chaitanya
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Implementation of collaborative multidisciplinary design optimization for conceptual design of a complex engineering product2016Inngår i: Concurrent Engineering - Research and Applications, ISSN 1063-293X, E-ISSN 1531-2003, Vol. 24, nr 3, s. 251-265Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study investigates the performance of the collaborative multidisciplinary design optimization framework and how it facilitates the knowledge integration process. The framework is used to design and optimize an innovative concept of a tidal water power plant. The case study helps to highlight the challenges that may occur during implementation. The result is presented as a modified framework with less implementation difficulties. The improved framework shows significant reduction in design time and improvement in collaborative design optimization for a design team. The geometry of the product is optimized to minimize weight and maximize the power generated by the turbine with respect to some mechanical constraints.

  • 82.
    Salaymeh, Ammar
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system.
    A New Conceptual Design Tool for General Aviation Aircraft (FLEX): A user-friendly computer implementation of classical design methods2018Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This report is a part of a thesis work at the division of Fluid and Mechatronic Systems(Flumes) at Linkoping University. The aim of this thesis is to build a robust, advanced, simple, easy to maintain, easy to develop and user-friendly program for the general aviation aircraft conceptual design. The program name is FLEX (FlumesExcel). The program was developed based on the most famous references in this eld such as Raymer [1], Gudmundsson [2] and Torenbeek [3]. Dierent methods and equations were evaluated to choose the best. In case there is no way to evaluate the methods, they were all implemented and the user has the ability to choose the desired one. Microsoft Excel was chosen to build the program and Excel VBA was used to build macros and functions in order to serve the objectives of the program. This report explains the used methods, the implementation way, and the program arrangement. It also shows how the results are presented in the program and provides the user with notes about the program using and its limits. The author supposes that the reader is familiar with the basic aerodynamic and aircraft design knowledge and nomenclatures. In order to not extend the report, some methods and theories are referred to the references without deep explanation. In case the used equations were derived by the author, they are explained in detail.

  • 83.
    Schmidt, Christiane
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    Andersson Granberg, Tobias
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    Polishchuk, Tatiana
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    Polishchuk, Valentin
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    CONVEX SECTORIZATION-A NOVEL INTEGER PROGRAMMING APPROACH2017Inngår i: 2017 INTEGRATED COMMUNICATIONS, NAVIGATION AND SURVEILLANCE CONFERENCE (ICNS), IEEE , 2017Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    We present a MIP-based airspace sectorization framework for Terminal Maneuvering Areas that can enforce convex sectors. The approach integrates an airspace complexity representation, and the resulting sectorizations have a balanced taskload. We present results for Stockholm TMA; and compare our results to convex sectorizations obtained by enumerating all possible topologies for a given number of sectors.

  • 84.
    Schminder, Jörg
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanisk värmeteori och strömningslära. Linköpings universitet, Tekniska fakulteten.
    Gårdhagen, Roland
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanisk värmeteori och strömningslära. Linköpings universitet, Tekniska fakulteten. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Nilsson, Elias
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanisk värmeteori och strömningslära. Linköpings universitet, Tekniska fakulteten. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Storck, Karl
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanisk värmeteori och strömningslära. Linköpings universitet, Tekniska fakulteten. SAAB Dynamics AB, Linköping, Sweden.
    Karlsson, Matts
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanisk värmeteori och strömningslära. Linköpings universitet, Tekniska fakulteten. Linköpings universitet, Centrum för medicinsk bildvetenskap och visualisering, CMIV.
    Development of a Cockpit-Pilot Model for Thermal Comfort Optimization During Long-Mission Flight2016Inngår i: AIAA Modeling and Simulation Technologies Conference San Diego, California, USA, AAAI Press, 2016Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The thermal comfort of a pilot is of crucial importance to maintain a high level ofconcentration and awareness during the entire ight mission. In this work a model for thethermal environment of the cockpit is developed and used as provider of input parametersto a thermoregulatory model, adopted from the literature, of a human. The cockpit-pilotmodel will be used to investigate and improve the thermal comfort for the pilot, particularlyduring longer ight missions. In the cockpit model a combination of lumped systems and nite dierence calculationsis used to obtain input parameters, which are provided to the pilot model. The body, withclothes, is divided into 16 segments and a nite dierence method is used to determine thetemperature distribution within these. Several physiological mechanisms are included inthe model. Simulations with dierent boundary conditions show that the models work properlyeven for longer missions.

  • 85.
    Schminder, Jörg
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanisk värmeteori och strömningslära. Linköpings universitet, Tekniska fakulteten.
    Hällqvist, Robert
    Systems Simulation and Concept Design, Saab Aeronautics, Linköping, Sweden.
    Eek, Magnus
    Systems Simulation and Concept Design, Saab Aeronautics, Linköping, Sweden.
    Gårdhagen, Roland
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanisk värmeteori och strömningslära. Linköpings universitet, Tekniska fakulteten.
    PILOT PERFORMANCE AND HEAT STRESS ASSESSMENTSUPPORT USING A COCKPIT THERMOREGULATORYSIMULATION MODEL2018Inngår i: ICAS congress proceeding, International Council of the Aeronautical Sciences , 2018, artikkel-id ICAS2018_0463Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Flights with high thermal loads inside the cockpitcan have a considerable impact on pilot physiologicaland psychological performance resultingin thermal discomfort, dehydration and fatigue.In this work, a Functional Mock-up Interface(FMI) based aircraft system simulator is utilizedwith intent to compute and predict thermalcomfort. The simulator can for example serve pilotsas a tool for heat stress and flight risk assessment,supporting their pre-flight planning or beused by engineers to design and optimize coolingefficiency during an early aircraft design phase.Furthermore, the presented simulator offers severaladvantages such as map based thermal comfortanalysis for a complete flight envelop, timeresolved mental performance prediction, and aflexible composability of the included models.

  • 86.
    Schminder, Jörg Paul Wilhelm
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanisk värmeteori och strömningslära. Linköpings universitet, Tekniska högskolan.
    Feasibility study of different methods for the use in aircraft conceptual design2012Independent thesis Advanced level (degree of Master (Two Years)), 80 poäng / 120 hpOppgave
    Abstract [en]

    The comparison of aerodynamic characteristics for a combat aircraft studywas addressed in this work. The thesis is a feasibility study which reviewsthe workload and output quality efficiency of different numerical and experimentalmethods often used during conceptual aircraft design.For this reason the Vortex Lattice Method (VLM), Euler or Reynolds-Averaged-Navier-Stokes (RANS) simulations were compared to the moreheavier Large Eddy Simulation (LES) which also has the capability to capturealso more complex flow physics, such as those that occur, for example,at high angles of attack. To be able to crosscheck the numerical results,the same static alpha sweep tests were executed in a tunnel. Thereby itwas discovered that it was quite challenging to reach the same values in thewater tunnel as those previously calculated in computational fluid dynamics(CFD) due to different technical issues.However it could be shown that LES simulations can be today a suitabletool for conceptual aircraft design, as they offer much higher levels ofaccuracy and give the designer the possibility to check the new study at anearly stage along the border of the aircraft’s flight envelope.

  • 87.
    Scholz, Dieter
    et al.
    Hamburg University of Applied Sciences, Germany.
    Seresinhe, Ravinka
    Cranfield University, UK.
    Staack, Ingo
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Lawson, Craig
    Cranfield University, UK.
    Fuel Consumption Due to Shaft Power Off-takes from The Engine2013Inngår i: Proceedings of the 4th International Workshop on Aircraft System Technologies / [ed] Frank Thielecke, Aachen: Shaker Verlag, 2013, s. 169-179Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    This paper looks at fuel consumption due to shaft power off-takes from the engine and the related increase in the aircraft’s fuel consumption. It presents a review and comparison of published and unpublished data on this kind of consumption. The paper presents results from the TURBOMATCH engine simulation model, calibrated to real world engine data. A generic equation is derived for the calculation of fuel consumption due to shaft power extraction. Main result is the shaft power factor kP found to be in the order of 0.002 N/W for a typical cruise flight. This yields an amazingly high efficiency for power generation by shaft power extraction from a turbo fan engine of more than 70 %.

  • 88.
    Schön, Sofia
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion.
    Design Space Exploration for Structural Aircraft Components: A method for using topology optimization in concept development2019Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    When building aircrafts, structural components must be designed for high strength, low cost, and easy assembly.To meet these conditions structural components are often based upon previous designs, even if a new component is developed.Refining previous designs can be a good way of preserving knowledge but can also limit the exploration of new design concepts.

    Currently the design process for structural aircraft components at SAAB is managed by design engineers. The design engineer is responsible for ensuring the design meets requirements from several different disciplines such as structural analysis, manufacturing, tool design, and assembly.Therefore, the design engineer needs to have good communication with all disciplines and an effective flow of information.

    The previous design is refined, it is then reviewed and approved by adjacent disciplines.Reviewing designs is an iterative process, and when several disciplines are involved it quickly becomes time consuming.Any time the design is altered it has to be reviewed once more by all disciplines to ensure the change is acceptable.So there is a need for further customizing the design concept to decrease the number of iterations when reviewing.

    Design Space Exploration DSE is a well known method to explore design alternatives before implementation and is used to find new concepts.This thesis investigates if DSE can be used to facilitate the design process of structural aircraft components and if it can support the flow of information between different disciplines.To find a suitable discipline to connect with design a prestudy is conducted, investigating what information affect structural design and how it is managed.The information flow is concluded in a schematic diagram where structural analysis is chosen as additional discipline.

    By using topology optimization in a DSE, design and structural analysis are connected.The design space can be explored with regards to structural constraints.The thesis highlights the possibilities of using DSE with topology optimization for developing structural components and proposes a method for including it in the design process.

  • 89.
    Sedov, Leonid
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    Polishchuk, Valentin
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Kommunikations- och transportsystem. Linköpings universitet, Tekniska fakulteten.
    Bulusu, Vishwanath
    Univ Calif Berkeley, CA 94720 USA.
    DECENTRALIZED SELF-PROPAGATING GROUND DELAY FOR UTM: CAPITALIZING ON DOMINO EFFECT2017Inngår i: 2017 INTEGRATED COMMUNICATIONS, NAVIGATION AND SURVEILLANCE CONFERENCE (ICNS), IEEE , 2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    We investigate a possible scheme for management of conflicts among autonomous unmanned aerial vehicles (UAVs) in high-density very low level (VLL) uncontrolled airspace. The drones are modeled as disks of a given radius, moving along prescribed trajectories planned without any centralized coordination. Thus, during the motion, the disks may potentially come into contact, which represents loss of separation between the drones. Two overlapping disks get enclosed by a larger disk serving as the protected zone for avoidance maneuvers of all the drones inside it. When the conflict is gone, the disk is deactivated and the UAVs continue towards their destinations. We simulate traffic demand and the evolution of the de-confliction zones over a geographic area and present statistics associated with functioning of the system with and without ground delay to avoid take offs into conflicts. The scheme shows promise and is a good approach to explore further in future work.

  • 90.
    Sethson, Magnus
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    A procedure for establishing an approximate helicopter performance model2011Inngår i: 3rd CEAS Air&Space Conference: CEAS 2011 Post-Conference Proceedings, Bologna, Italy: Con-fine Ed. Monghidoro , 2011, s. 952-959Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    The main performance characteristics of a heli- copter is its fuel consumption. This paper re- ports the current state in an ongoing project seeking a fast and approximative implementa- tion of mathematical models for helicopter per- formance predictions, primarily in terms of fuel consumption. The model is limited to a subset of the normal operation modes, only including hover, climb and forward. Also, the focus is on smaller rotors, i.e. sub-scale rotors in the range of 1.5m to 4.0m in diameter as used in unmanned airborne vehicles (VTOL-UAV). The presented work consists of three parts; the heli- copter performance mathematical model and the numerical optimization method used for dealing with its implicit nature, the approximation grid scheme and the simulation of flight paths. The overall objective of the project is to establish an computational efficient approximative model us- able for onboard condition monitoring of the he- licopter performance and fuel consumption. 

  • 91.
    Shetty, Sandeep
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling. Linköpings universitet, Tekniska fakulteten.
    Optimization of Vehicle Structures under Uncertainties2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Advancements in simulation tools and computer power have made it possible to incorporate simulation-based structural optimization in the automotive product development process. However, deterministic optimization without considering uncertainties such as variations in material properties, geometry or loading conditions might result in unreliable optimum designs. 

    In this thesis, the capability of some established approaches to perform design optimization under uncertainties is assessed, and new improved methods are developed. In particular, vehicle structural problems which involve computationally expensive Finite Element (FE) simulations, are addressed.

    The first paper focuses on the evaluation of robustness, given some variation in input parameters, the capabilities of three well-known metamodels are evaluated. In the second paper, a comparative study of deterministic, reliability-based and robust design optimization approaches is performed. It is found that the overall accuracy of the single-stage (global) metamodels, which are used in the above study, is acceptable for deterministic optimization. However, the accuracy of performance variation prediction (local sensitivity) must be improved. In the third paper, a decoupled reliability-based design optimization (RBDO) approach is presented. In this approach, metamodels are employed for the deterministic optimization only while the uncertainty analysis is performed using FE simulations in order to ensure its accuracy.

    In the fifth paper, two new sequential sampling strategies are introduced that aim to improve the accuracy of the metamodels efficiently in critical regions. The capabilities of the methods presented are illustrated using analytical examples and a vehicle structural application.

    It is important to accurately represent physical variations in material properties since these might exert a major influence on the results. In previous work these variations have been treated in a simplified manner and the consequences of these simplifications have been poorly understood. In the fourth paper, the accuracy of several simple methods in representing the real material variation has been studied. It is shown that a scaling of the nominal stress-strain curve based on the Rm scatter is the best choice of the evaluated choices, when limited material data is available.

    In this thesis work, new pragmatic methods for non-deterministic optimization of large scale vehicle structural problems have been developed. The RBDO methods developed are shown to be flexible, more efficient and reasonably accurate, which enables their implementation in the current automotive product development process.

    Delarbeid
    1. Robustness study of a hat profile beam made of boron steel subjected to three point bending
    Åpne denne publikasjonen i ny fane eller vindu >>Robustness study of a hat profile beam made of boron steel subjected to three point bending
    2016 (engelsk)Inngår i: International Journal of Vehicle Systems Modelling and Testing, ISSN 1745-6436, E-ISSN 1745-6444, nr 3, s. 252-270Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    It is essential to account for variations in the manufacturing process and in loading conditions when improving the robustness and reliability of a product’s design. A finite element study of the robustness of a hat profile beam made from boron steel subjected to a three point bending load is presented, and an approach to incorporate the variations investigated is demonstrated. Fracture risk factors and the maximum deflection of the beam are the measured responses. Spatial variation of the sheet thickness is considered in the forming simulations, along with other input variations. Stress-strain relations from tensile tests have been used in the robustness analyses to represent the variation in material properties. Furthermore, validations of four metamodels have been performed. Both the responses measured were found to be sensitive to input variations. Separate metamodels were created for each risk prone zone in order to improve the performance of the metamodels for risk factor responses.

    sted, utgiver, år, opplag, sider
    Bucks: InderScience Publishers, 2016
    Emneord
    Robustness analysis; Monte Carlo analysis; metamodel; boron steel; fracture risk factor
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-103690 (URN)10.1504/IJVSMT.2016.080880 (DOI)
    Tilgjengelig fra: 2014-01-23 Laget: 2014-01-23 Sist oppdatert: 2017-12-06bibliografisk kontrollert
    2. Multiobjective reliability-based and robust design optimisation for crashworthiness of a vehicle side impact
    Åpne denne publikasjonen i ny fane eller vindu >>Multiobjective reliability-based and robust design optimisation for crashworthiness of a vehicle side impact
    2015 (engelsk)Inngår i: International Journal of Vehicle Design, ISSN 0143-3369, E-ISSN 1741-5314, Vol. 67, nr 4, s. 347-367Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Optimisation of vehicle design is necessary to meet increased safety requirements, new emission regulations, and to deal with competition in the global market, etc. However, optimised design using classical optimisation techniques with deterministic models might not meet the desired performance level or might fail in extreme events in real life owing to uncertainties in the design parameters and loading conditions. Consequently, it is essential to account for uncertainties in a systematic manner to generate a robust and reliable design. In this paper, an approach to perform multiobjective, reliability-based, and robust design optimisation is presented using a vehicle side impact crashworthiness application. Metamodels have been used in the optimisation process to decrease computational effort. Variations in material properties, thicknesses, loading conditions, and B-pillar heat-affected zone material strength have been considered for the stochastic optimisation. A comparative study of deterministic, reliability-based, and robust optimisation approaches is performed.

    sted, utgiver, år, opplag, sider
    InderScience Publishers, 2015
    Emneord
    Multiobjective optimisation; robust optimisation; reliabilitybased optimisation; crashworthiness; Monte Carlo analysis; metamodel; boron steel; fracture risk factor
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-103691 (URN)10.1504/IJVD.2015.070410 (DOI)000359461500002 ()
    Tilgjengelig fra: 2014-01-23 Laget: 2014-01-23 Sist oppdatert: 2017-12-06bibliografisk kontrollert
    3. Efficient reliability-based optimization using a combined metamodel and FE-based strategy
    Åpne denne publikasjonen i ny fane eller vindu >>Efficient reliability-based optimization using a combined metamodel and FE-based strategy
    2014 (engelsk)Inngår i: Engineering Optimization IV - Proceedings of the 4th International Conference on Engineering Optimization, ENGOPT 2014 / [ed] Rodrigues H.C., Herskovits J., Soares C.M.M., Guedes J.M., Araujo A.L., Folgado J.O., Moleiro F., Madeira J.F.A., Leiden, The Netherlands: CRC Press, 2014, s. 471-478Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    It is essential to consider the uncertainties in design variables of an optimization process in order to create a reliable design. The computational effort required to perform reliability-based optimization of complex engineering problems is very high and most recent studies have used metamodels in order to reduce the computational effort.An efficient decoupled sequential reliability-based optimization using the combination of metamodel-based strategy and FE-based strategy is presented in this paper. Optimization loop and stochastic analysis loops are completely decoupled. Stochastic analysis is performed at the end of each optimization iteration and at the beginning of the first iteration only. In each optimization iteration, the standard deviation of constraint functions from the previous iteration is used. The stochastic analysis is performed using an FE-based Monte Carlo method,whereas metamodels have been utilized for the optimization. This approach is demonstrated using two engineering examples.

    sted, utgiver, år, opplag, sider
    Leiden, The Netherlands: CRC Press, 2014
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-133197 (URN)2-s2.0-84941985436 (Scopus ID)
    Konferanse
    ENGOPT 2014 - 4th International Conference on Engineering optimization, 8-11 September, Instituto Superioe Tecnico, Lissabon, Portugal
    Tilgjengelig fra: 2016-12-14 Laget: 2016-12-14 Sist oppdatert: 2018-01-13bibliografisk kontrollert
    4. An evaluation of simple techniques to model the variation in strain hardening behavior of steel
    Åpne denne publikasjonen i ny fane eller vindu >>An evaluation of simple techniques to model the variation in strain hardening behavior of steel
    2017 (engelsk)Inngår i: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 55, nr 3, s. 945-957Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    It is important to consider variations in material parameters in the design of automotive structures in order to obtain a robust and reliable design. However, expensive tests are required to gain complete knowledge of the material behavior and its associated variation. Consequently, due to time and cost constraints, simplified material scatter modeling techniques based on scatter data of typical material properties provided by the material suppliers are used at early design stages in simulation-based robustness studies. The aim of this paper is to study the accuracy of the simplified scatter modeling methods in representing the real material variation. The simplified scatter modeling methods are evaluated by comparing the material scatter obtained by them to the scatter obtained by complete tensile tests, which are obtained after detailed timeconsuming experimental investigations. Furthermore, an accuracy assessment is carried out based on selected responses from an axially-crushed, square tube made from DP600 steel.

    sted, utgiver, år, opplag, sider
    Bonn: Springer, 2017
    Emneord
    Flow curve, Material scatter, Stochastic simulation, Tensile test
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-133198 (URN)10.1007/s00158-016-1547-6 (DOI)000398114200014 ()
    Merknad

    Funding agencies: Robust and multidisciplinary optimization of automotive structures Project - Vinnova FFI; Volvo Car Corporation

    Tilgjengelig fra: 2016-12-14 Laget: 2016-12-14 Sist oppdatert: 2017-04-20bibliografisk kontrollert
  • 92.
    Shetty, Sandeep
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling. Linköpings universitet, Tekniska fakulteten. Painted Body and Closures, Volvo Car Corporation.
    Nilsson, Larsgunnar
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Mekanik och hållfasthetslära. Linköpings universitet, Tekniska fakulteten.
    An evaluation of simple techniques to model the variation in strain hardening behavior of steel2017Inngår i: Structural and multidisciplinary optimization (Print), ISSN 1615-147X, E-ISSN 1615-1488, Vol. 55, nr 3, s. 945-957Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    It is important to consider variations in material parameters in the design of automotive structures in order to obtain a robust and reliable design. However, expensive tests are required to gain complete knowledge of the material behavior and its associated variation. Consequently, due to time and cost constraints, simplified material scatter modeling techniques based on scatter data of typical material properties provided by the material suppliers are used at early design stages in simulation-based robustness studies. The aim of this paper is to study the accuracy of the simplified scatter modeling methods in representing the real material variation. The simplified scatter modeling methods are evaluated by comparing the material scatter obtained by them to the scatter obtained by complete tensile tests, which are obtained after detailed timeconsuming experimental investigations. Furthermore, an accuracy assessment is carried out based on selected responses from an axially-crushed, square tube made from DP600 steel.

  • 93.
    Singh, Aakash Narender
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system.
    Govindharajan, Vijay
    Automated generic parameterized design of aircraft fairing and windshield2012Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The process of design is time consuming and result oriented. There is always a better scope for any design that reduces the time with better precision. Considering this as a major factor during design process, two of the vital parts of the aircraft conceptual design are taken into account where a lot of time can be saved. Major components considered in this work are fairings for the lift generating surfaces and cockpit windshield. In this work the major inference is to reduce the time spent on the initial conceptual design.

    The two components designed in this work are fairings and windshield. The fairing design in this work provides a flexible template which can be used for various fuselage and wing configurations for transport aircrafts. The windshield is classified into two types in this work, flat and blend windshield. Both the type of windshields can be implemented on appropriate fuselage.

    Both the components are designed to be implemented in single pilot as well as double pilot aircrafts. They also have parameters which can be modified according to the user requirement. The changes in the parameters provide the change in shape, size and volume of the components.

    The software used for this is CATIA V5. The process is carried out using two automation methods available in CATIA namely Power-Copy and Knowledge pattern. A comparison between the effectiveness of two automation methods used in this work is performed.

  • 94.
    Sobron, Alejandro
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Design and Testing of a Flight Control System for Unstable Subscale Aircraft2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The primary objective of this thesis was to study, implement, and test low-cost electronic flight control systems (FCS) in remotely piloted subscale research aircraft with relaxed static longitudinal stability. Even though this implementation was carried out in small, simplified test-bed aircraft, it was designed with the aim of being installed later in more complex demonstrator aircraft such as the Generic Future Fighter concept demonstrator project. The recent boom of the unmanned aircraft market has led to the appearance of numerous electronic FCS designed for small-scale vehicles and even hobbyist-type model aircraft. Therefore, the purpose was not to develop a new FCS from scratch, but rather to take advantage of the available technology and to examine the performance of different commercial off-the-shelf (COTS) low-cost systems in statically unstable aircraft models. Two different systems were integrated, calibrated and tested: a simple, gyroscope-based, single-axis controller, and an advanced flight controller with a complete suite of sensors, including a specifically manufactured angle-of-attack transducer. A flight testing methodology and appropriate flight-test data analysis tools were also developed. The satisfactory results are discussed for different flight control laws, and the controller tuning procedure is described. On the other hand, the different test-bed aircraft were analysed from a theoretical point of view by using common aircraft-design methods and conventional preliminary-design tools. The theoretical models were integrated into a flight dynamics simulator, which was compared with flight-test data obtaining a reasonable qualitative correlation. Possible FCS modifications are discussed and some future implementations are proposed, such as the integration of the angle-of-attack in the control laws.

  • 95.
    Sobron, Alejandro
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    On Subscale Flight Testing: Applications in Aircraft Conceptual Design2018Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Downscaled physical models, also referred to as subscale models, have played an essential role in the investigation of the complex physics of flight until the recent disruption of numerical simulation. Despite the fact that improvements in computational methods are slowly pushing experimental techniques towards a secondary role as verification or calibration tools, real-world testing of physical prototypes still provides an unmatched confidence. Physical models are very effective at revealing issues that are sometimes not correctly identified in the virtual domain, and hence can be a valuable complement to other design tools. But traditional wind-tunnel testing cannot always meet all of the requirements of modern aeronautical research and development. It is nowadays too expensive to use these scarce facilities to explore different design iterations during the initial stages of aircraft development, or to experiment with new and immature technologies.

    Testing of free-flight subscale models, referred to as Subscale Flight Testing (SFT), could offer an affordable and low-risk alternative for complementing conventional techniques with both qualitative and quantitative information. The miniaturisation of mechatronic systems, the advances in rapid-prototyping techniques and power storage, as well as new manufacturing methods, currently enable the development of sophisticated test objects at scales that were impractical some decades ago. Moreover, the recent boom in the commercial drone industry has driven a quick development of specialised electronics and sensors, which offer nowadays surprising capabilities at competitive prices. These recent technological disruptions have significantly altered the cost-benefit function of SFT and it is necessary to re-evaluate its potential in the contemporary aircraft development context.

    This thesis aims to increase the comprehension and knowledge of the SFT method in order to define a practical framework for its use in aircraft design; focusing on low-cost, short-time solutions that don’t require more than a small organization and few resources. This objective is approached from a theoretical point of view by means of an analysis of the physical and practical limitations of the scaling laws; and from an empirical point of view by means of field experiments aimed at identifying practical needs for equipment, methods, and tools. A low-cost data acquisition system is developed and tested; a novel method for semi-automated flight testing in small airspaces is proposed; a set of tools for analysis and visualisation of flight data is presented; and it is also demonstrated that it is possible to explore and demonstrate new technology using SFT with a very limited amount of economic and human resources. All these, together with a theoretical review and contextualisation, contribute to increasing the comprehension and knowledge of the SFT method in general, and its potential applications in aircraft conceptual design in particular.

    Delarbeid
    1. Design and Testing of a Low-Cost Flight Control and Data Acquisition System for Unstable Subscale Aircraft
    Åpne denne publikasjonen i ny fane eller vindu >>Design and Testing of a Low-Cost Flight Control and Data Acquisition System for Unstable Subscale Aircraft
    2016 (engelsk)Inngår i: Proceedings of the 30th Congress of The International Council of the Aeronautical Sciences (ICAS), September 25-30, Daejeon, South Korea., Bonn: The International Council of the Aeronautical Sciences , 2016Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    Current research on subscale flight testing methodologies at Linköping University is performed by using various platforms, some of them with advanced configurations. These have been previously flown in open-loop under direct commands from the pilot. However, the interest in flying some of these platforms with relaxed stability and the investigation of multi-surface control allocation techniques motivated the implementation of a simple low-cost flight control system based on commercial-off-the-shelf components. The work described in this paper evaluates the simplest available solutions that provide control augmentation for small, longitudinally unstable, free-flying models. This work also tries to define a reliable, fail-safe system architecture that can be implemented in more advanced platforms. Moreover, data acquisition and analysis are evaluated with the aim of applying system identification techniques.

    sted, utgiver, år, opplag, sider
    Bonn: The International Council of the Aeronautical Sciences, 2016
    Emneord
    subscale, flight testing, flight control, data acquisition, relaxed stability
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-142393 (URN)978-3-932182-85-3 (ISBN)
    Konferanse
    30th Congress of The International Council of the Aeronautical Sciences (ICAS), Daejeon, Korea, September 25-30, Daejeon, South Korea.
    Prosjekter
    MSDEMO
    Tilgjengelig fra: 2017-10-30 Laget: 2017-10-30 Sist oppdatert: 2018-11-05
    2. Subscale Flight Testing of a Generic Fighter Aircraft
    Åpne denne publikasjonen i ny fane eller vindu >>Subscale Flight Testing of a Generic Fighter Aircraft
    Vise andre…
    2016 (engelsk)Inngår i: Proceedings of the 30th Congress of the International Council of the Aeronautical Sciences (ICAS) / [ed] The International Council of the Aeronautical Sciences, Bohn, 2016Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    Recent technological advances in mechatronics enhance the possibilities of utilizing subscale flight testing as a tool in the development of aircraft. This paper reports the current status of a joint Swedish-Brazilian research project aiming at exploring these possibilities. A 13\% scale fighter aircraft is used as a test bench for developing methods and procedures for data acquisition. The aircraft is equipped with an instrumentation system assembled from off the shelf components as well as open source hardware and software.

    sted, utgiver, år, opplag, sider
    Bohn: , 2016
    Emneord
    subscale, free flight test, demonstrator, data acquisition
    HSV kategori
    Identifikatorer
    urn:nbn:se:liu:diva-142398 (URN)978-3-932182-85-3 (ISBN)
    Konferanse
    30th Congress of the International Council of the Aeronautical Sciences (ICAS), September 25-30, Daejeon, South Korea
    Prosjekter
    MSDEMO
    Tilgjengelig fra: 2017-10-30 Laget: 2017-10-30 Sist oppdatert: 2018-11-05
  • 96.
    Sobron, Alejandro
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Lundström, David
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Krus, Petter
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Jouannet, Christopher
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Sandoval Goez, Luiz Carlos
    Instituto Tecnológico de Aeronáutica, Brasil.
    Flight test design for remotely-piloted aircraft in confined airspace2017Inngår i: 6th CEAS Air and Space Conference, Aerospace Europe, 16-20 October, 2017, Bucharest, Romania. / [ed] The Council of European Aerospace Societies, Brussels, 2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Thispaper presents various techniques and procedures that aim to simplify flighttesting of fixed-wing, remotely-piloted aircraft with the purposes ofperformance evaluation and system identification. These methods have beenspecifically developed for flight within visual line-of-sight, a type ofoperation that limits the available airspace severely but offers major costadvantages considering the current regulations for unmanned flight in mostWestern countries.

  • 97.
    Sobron, Alejandro
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Lundström, David
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Larsson, Roger
    Linköpings universitet, Institutionen för systemteknik, Reglerteknik. Linköpings universitet, Tekniska fakulteten.
    Krus, Petter
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Jouannet, Christopher
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Methods for efficient flight testing and modelling of remotely piloted aircraft within visual line-of-sight2018Inngår i: Proceedings of the 31st Congress of The International Council of the Aeronautical Sciences (ICAS), September 9-14 2018, Belo Horizonte, Brazil. / [ed] The International Council of the Aeronautical Sciences, Bohn, 2018Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Remotely piloted scaled models not only serve as convenient low-risk flying test-beds but also can provide useful data and increase confidence in an eventual full-scale design. Nevertheless, performing advanced flight tests in a safe and cost-effective manner is often a challenge for organizations with limited resources. A typical scenario is testing within visual line-of-sight at very low altitude, a type of operation that offers major cost advantages at the expense of a reduced available airspace. This paper describes some of the authors' work towards efficient performance evaluation and system identification of fixed-wing, remotely piloted aircraft under these challenging conditions. Results show that certain techniques, manoeuvre automation, and platform-optimised multisine input signals can improve the flight test efficiency and the modelling process. It is also probable that some of the benefits observed here could be extrapolated to flight testing beyond visual line-of-sight or even to full-scale flight testing.

  • 98.
    Sobron, Alejandro
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Lundström, David
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Staack, Ingo
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Krus, Petter
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska fakulteten.
    Design and Testing of a Low-Cost Flight Control and Data Acquisition System for Unstable Subscale Aircraft2016Inngår i: Proceedings of the 30th Congress of The International Council of the Aeronautical Sciences (ICAS), September 25-30, Daejeon, South Korea., Bonn: The International Council of the Aeronautical Sciences , 2016Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Current research on subscale flight testing methodologies at Linköping University is performed by using various platforms, some of them with advanced configurations. These have been previously flown in open-loop under direct commands from the pilot. However, the interest in flying some of these platforms with relaxed stability and the investigation of multi-surface control allocation techniques motivated the implementation of a simple low-cost flight control system based on commercial-off-the-shelf components. The work described in this paper evaluates the simplest available solutions that provide control augmentation for small, longitudinally unstable, free-flying models. This work also tries to define a reliable, fail-safe system architecture that can be implemented in more advanced platforms. Moreover, data acquisition and analysis are evaluated with the aim of applying system identification techniques.

  • 99.
    Sohaib, Muhammad
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion.
    Parameterized Automated Generic Model for Aircraft Wing Structural Design and Mesh Generation for Finite Element Analysis2011Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This master thesis work presents the development of a parameterized automated generic model for the structural design of an aircraft wing. Furthermore, in order to perform finite element analysis on the aircraft wing geometry, the process of finite element mesh generation is automated.

    Aircraft conceptual design is inherently a multi-disciplinary design process which involves a large number of disciplines and expertise. In this thesis work, it is investigated how high-end CAD software‟s can be used in the early stages of an aircraft design process, especially for the design of an aircraft wing and its structural entities wing spars and wing ribs.

    The generic model that is developed in this regard is able to automate the process of creation and modification of the aircraft wing geometry based on a series of parameters which define the geometrical characteristics of wing panels, wing spars and wing ribs.Two different approaches are used for the creation of the generic model of an aircraft wing which are “Knowledge Pattern” and “PowerCopy with Visual Basic Scripting” using the CATIA V5 software. A performance comparison of the generic wing model based on these two approaches is also performed.

    In the early stages of the aircraft design process, an estimate of the structural characteristic of the aircraft wing is desirable for which a surface structural analysis (using 2D mesh elements) is more suitable. In this regard, the process of finite element mesh generation for the generic wing model is automated. The finite element mesh is generated for the wing panels, wing spars and wing ribs. Furthermore, the finite element mesh is updated based on any changes in geometry and the shape of the wing panels, wing spars or wing ribs, and ensure that all the mesh elements are always properly connected at the nodes. The automated FE mesh generated can be used for performing the structural analysis on an aircraft wing.

  • 100.
    Staack, Ingo
    et al.
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Chaitanya Manjula, Raghu
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Berry, Patrick
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Melin, Tomas
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Amadori, Kristian
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion. Linköpings universitet, Tekniska högskolan.
    Jouannet, Christopher
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Lundström, David
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Krus, Petter
    Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Fluida och mekatroniska system. Linköpings universitet, Tekniska högskolan.
    Parametric Aircraft Conceptual Design Space2012Inngår i: Prceedings of the 28th International Congress of the Aeronautical Sciences, 2012Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    This paper presents the development of a design framework for the initial conceptual design phase. The focus in this project is on a flexible database in XML format, together with close integration of automated CAD, and other tools, which allows the developed geometry to be used directly in the subsequent preliminary design phase. The database and the geometry are also described and an overview is given of included tools like aerodynamic analysis and weight estimation.

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