Characterizing vortices in planar slices of turbulent flow fields using two efficient methods

Determining the radius, circulation and swirl intensity of vortices in planar slices of turbulent flow fields that is simple, robust and nonselective has been developed. The used methods in this work compute a rigid-bodyrotation vorticity, similar to the approach of Kolάř [1] and λci criteria [2]. In order to distinguish swirling motions of vortices from shearing motions that is not significantly contaminated by shear, these methods are employed. By using this rigid-body-rotation vorticity in conjunction with the Oseen vortex model as a vortex template and λci criteria, the radius and the circulation of all detected vortices are determined with no discrimination upon individual vortex properties. It has been shown that these methods can effectively identify the vortices. Hence, these techniques would be useful tools to detect and measure the swirling motion of vortices.

کلیدواژه ها:

vortices ، turbulent flow ، Particle ImageVelocimetry ،