Flow Visualization for Vortex Structures in the Wake of the Flat Parallel Plates with Periodic Disturbance

A wake without reverse flow like a flat plate wake is a very unstable flow, and the vortex structure in such a wake is affected by various disturbances in main flow. In this study, the vortex formation process in the wake of the flat parallel plates with periodic disturbance was shown by using flow visualization technique in order to control the wake structures by disturbance frequency. As a result, it was confirmed that disturbance frequency, particularly frequency combinations in the case of bimodal disturbance affect wake periodicity, vortex size, vortex shape and downstream location of vortex formation / deformation.