EXTRACTING 3D VORTICES IN TURBULENT FLUID-FLOW

This paper presents a computational framework to extract salient patte rns, called vortex structures, from 3D turbulent fluid flows. These st ructures can be characterized as regions of dominating rotational moti on in the velocity fields and intensity concentrations in the correspo nding vorticity fields. A pointwise linear representation is employed to approximate the kinematics of the flow field, and the fluid motion is classified according to motion analysis or topological patterns. Th e regions of vortex structures are identified as those dominated by ro tational motion or those of focus-type singularity. The 2D vortices, a s a special case of 3D vortices, are detected by searching for regions of vorticity concentrations.