Control of vortex shedding from a circular cylinder using imposed transverse magnetic field

Abstract

Purpose

The purpose of this paper is to simulate the flow of a conducting fluid past a circular cylinder placed centrally in a channel subjected to an imposed transverse magnetic field to study the effect of a magnetic field on vortex shedding at different Reynolds numbers varying from 50 to 250.

Design/methodology/approach

The two‐dimensional incompressible laminar viscous flow equations are solved using a second‐order implicit unstructured collocated grid finite volume method.

Findings

An imposed transverse magnetic field markedly reduces the unsteady lift amplitude indicating a reduction in the strength of the shed vortices. It is observed that the periodic vortex shedding at the higher Reynolds numbers can be completely suppressed if a sufficiently strong magnetic field is imposed. The required magnetic field strength to suppress shedding increases with Reynolds number. The simulation shows that the separated zone behind the cylinder in a steady flow is reduced as the magnetic field strength is increased.

Originality/value

In this paper, due attention is given to resolve and study the unsteady cylinder wake and its interaction with the shear‐layer on the channel wall in the presence of a magnetic field. A critical value of the Hartmann number for complete suppression of the shedding at a given Reynolds number is found.

Citation

Singha, S. and Sinhamahapatra, K.P. (2011), "Control of vortex shedding from a circular cylinder using imposed transverse magnetic field", International Journal of Numerical Methods for Heat & Fluid Flow, Vol. 21 No. 1, pp. 32-45. https://doi.org/10.1108/09615531111095058