Two-dimensional Time-dependent Vortex Regions based on the Acceleration Magnitude
2011 (English)In: IEEE Transactions on Visualization and Computer Graphics, ISSN 1077-2626, E-ISSN 1941-0506, Vol. 17, no 12, 2080-2087 p.Article in journal (Refereed) Published
Acceleration is a fundamental quantity of flow fields that captures Galilean invariant properties of particle motion. Considering the magnitude of this field, minima represent characteristic structures of the flow that can be classified as saddle- or vortex-like. We made the interesting observation that vortex-like minima are enclosed by particularly pronounced ridges. This makes it possible to define boundaries of vortex regions in a parameter-free way. Utilizing scalar field topology, a robust algorithm can be designed to extract such boundaries. They can be arbitrarily shaped. An efficient tracking algorithm allows us to display the temporal evolution of vortices. Various vortex models are used to evaluate the method. We apply our method to two-dimensional model systems from computational fluid dynamics and compare the results to those arising from existing definitions.
Place, publisher, year, edition, pages
2011. Vol. 17, no 12, 2080-2087 p.
Vortex regions, time-dependent flow fields, feature extraction.
Computer Vision and Robotics (Autonomous Systems)
IdentifiersURN: urn:nbn:se:liu:diva-127672DOI: 10.1109/TVCG.2011.249PubMedID: 22034326OAI: oai:DiVA.org:liu-127672DiVA: diva2:926363