Extraktion von Wirbelstrukturen in 3D Strömungsfeldern [Elektronische Ressource] / von Jan Sahner

EXTRACTION OF VORTEX STRUCTURESIN 3D FLOW FIELDSDissertationzur Erlangung des akademischen GradesDoktoringenieur (Dr.-Ing.)angenommen durch die Fakultät für Informatikder Otto-von-Guericke-Universität Magdeburgvon Dipl.-Math. Jan Sahnergeboren am 19. März 1977 in EckernfördeGutachter:Prof. Dr. Holger TheiselProf. Dr. Gerik ScheuermannProf. Dr. Ronny PeikertMagdeburg, den 30. April 2009Für Uta, Adi, Ferdi und Ani.AbstractThe analysis of flow datasets becomes more and more challenging due to the sheer datasize produced by modern simulations and experimental measurements. Feature extrac-tion is necessary for a significant reduction of data fluid mechanicists are faced with.Among a variety of interesting flow features, vortex features are the most prominent.This thesis is devoted to the development of algorithms for vortex feature extractionin 3D and 3D time dependent flow fields. It contains advances in two categories: vortexfeatures defined by swirling motion, and vortex features defined by extremal structuresof scalar feature indicators. For the former, we present a novel extraction approachfor swirling stream line motion cores in snapshots of the flow field and show howthose structures can be tracked in time by appropriate feature flow fields. While thisapproach is based on stream lines, we extend this work to path lines to extract thecenter lines of swirling particle motion for the first time.