Delocalized Unsteady Vortex Region Detectors

In this paper we discuss generalizations of instantaneous, local vortex criteria. We incorporate information on spatial context and temporal development into the detection process. The presented method is generic in so far that it can extend any given Eulerian criterion to take the Lagrangian approach into account. Furthermore, we present a visual aid to understand and steer the feature extraction process. We show that the delocalized detectors are able to distinguish between connected vortices and help understanding regions of multiple interacting vortex structures. The delocalized detectors extract smoother structures and reduce noise in the vortex detection result.

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