Hierarchical Watershed Ridges for Visualizing Lagrangian Coherent Structures
نویسندگان
چکیده
Lagrangian coherent structures provide insight into unsteady fluid flow, but their construction has posed many challenges. These structures can be characterized as ridges of a field, but their local definition utilizes an ambiguous eigenvector direction which can point in one of two directions, and its disambiguation can lead to noise and other problems. We overcome these issues with an application of a global ridge definition, applied using the hierarchical watershed transformation. We show results on a mathematical flow model and a simulated vascular flow dataset indicating the watershed method produces less noisy Lagrangian coherent structures.
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