CONTROL OF WAKE AND VORTEX SHEDDING BEHIND SOLID CIRCULAR OBSTACLE BY MAGNETOHYDRODYNAMICS

Abstract

Control of vortex shedding leads to a reduction in the unsteady forces acting on the bluff bodies and can significantly reduce their vibrations. In this paper, the finite volume method (FVM) is used to simulate the flow around and through twodimensional circular obstacle. An external magnetic field is applied to control the wake behind the obstacle and also to suppress the vortex shedding phenomena. Maxwell equations are applied to provide the coupling between the flow field and the magnetic field. The range of Stuart (N) and Reynolds (Re) numbers are 0-10 and 1-200, respectively. The effects of magnetic field on control of wake structure behind the obstacle are investigated in details. It is found that for higher Stuart number (i.e. N=5), drag coefficient increases rapidly by using magnetic field.

Keywords

• wake; magnetic field; Stuart number; vortex shedding

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