Simulation of vortex shedding from a square cylinder in oscillating channel flow

Abstract

Laminar vortex shedding of a square cylinder mounted between two parallel walls are numerically simulated by using a finite volunme method based on a linear upwind differencing scheme and SIMPLER algorithm. The unsteady terms are approximated by a two-step fully-implicit backward scheme. The lock-on phenomena in an oscillating flow as well as the vortex shedding in a steady flow are investigated. The values of Strouhal number in the steady uniform flow are reasonably predicted with accuracy by the present numerical method. The frequency range of the incoming flow for the lock-on appear is well simulated. When the flow is loked-on, the shedding frequency is half of the incoming flow frequency. The structural characteristics of shedding vortex in the lock-on range is discussed in the present paper.