Author(s): Huai Chen; Danxun Li; Qigang Chen; Xingkui Wang
Linked Author(s): Qigang Chen
Keywords: PIV; Cavity flow; Reynolds number; Vortex; Reynolds stress
Abstract: The paper presents an experimental study of vortex population and Reynolds stress in a cavity flow at various Reynolds numbers ranging from 240 to 4190. The experiments are based on time-resolved measurement of instantaneous velocities in the mid-perpendicular section of the cavity with particle image velocimetry (PIV). By using the swirling strength criterion, instantaneous vortices are extracted and populations of both counter-clockwise (CCW) and clockwise (CW) vortices are computed. Results reveal that CCW and CW vortices tend to reside in separated zones in the cavity, and CCW vortex exhibits a much higher population than the CW vortex. The vortex generation region remains close to the impinging zone at laminar inflow and migrates away as the inflow turns turbulent. The correlation between Reynolds stress and vortex population becomes obscure as Reynolds number increases.
Year: 2013