Reconstruction of velocity data using adjoint optimization
2004 (English)Licentiate thesis, comprehensive summary (Other academic)
In many application areas there is a growing interest in data assimilation or data reconstruction. Data assimilation is a process for integrating observed or measured data into a physical model. The problem originates from a vast array of different topics: traditionally in metereological and oceanographic modelling, and recently from non-invasive medical measurement devices such as magnetic resonance imaging. The measured data may contain inaccurancies and random noise, given with low spatial and/or temporal resolution.
This thesis presents a method for solving reconstruction problems in fluid dynamics using optimal control theory. The problem considered here includes a known partial differential equation and some spatially and temporarily sparsely distributed data with an unknown initial state. From a given velocity field uδ, a flow field u is determined which satisfies a given system of partial differential equations and minimizes || u - u*|| L2. The function u(x,t) is known at the boundary and the initial condition u0(x) is used as design variable. The optimization problem is solved using adjoint formulation.
Place, publisher, year, edition, pages
Linköping: Linköpings universitet , 2004. , 8 p.
Linköping Studies in Science and Technology. Thesis, ISSN 0280-7971 ; 1096
IdentifiersURN: urn:nbn:se:liu:diva-23162Local ID: 2566ISBN: 91-7373-969-3OAI: oai:DiVA.org:liu-23162DiVA: diva2:243476
2004-05-25, Glashuset, Hus B, Linköpings universitet, Linköpings, 13:15 (Swedish)
Gustafsson, Nils, Professor
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