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Feature Extraction of Separation and Attachment Lines *
April-June 1999 (vol. 5 no. 2)
pp. 135-144

Abstract—Separation and attachment lines are topologically significant curves that exist on 2D surfaces in 3D vector fields. Two algorithms are presented, one point-based and one element-based, that extract separation and attachment lines using eigenvalue analysis of a locally linear function. Unlike prior techniques based on piecewise numerical integration, these algorithms use robust analytical tests that can be applied independently to any point in a vector field. The feature extraction is fully automatic and suited to the analysis of large-scale numerical simulations. The strengths and weaknesses of the two algorithms are evaluated using analytic vector fields and also results from computational fluid dynamics (CFD) simulations. We show that both algorithms detect open separation lines–a type of separation that is not captured by conventional vector field topology algorithms.

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Index Terms:
Vector field visualization, vector field topology, flow visualization, feature detection, flow separation, separation line.
David N. Kenwright, Chris Henze, Creon Levit, "Feature Extraction of Separation and Attachment Lines *," IEEE Transactions on Visualization and Computer Graphics, vol. 5, no. 2, pp. 135-144, April-June 1999, doi:10.1109/2945.773805
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