Effects of gravity modulation on convection in a horizontal annulus (Q860083)

The authors examine buoyancy-induced convection in a horizontal concentric annulus of finite length. The effect of gravity modulation under the conditions of microgravity have been considered. The gravitational acceleration is taken in the form of a steady component superimposed by a fluctuating component. The governing equations have been expressed in terms of vorticity and vector potentials. Detailed numerical investigations have been done for large, moderate and narrow gap annulus. A comparative study of convection and secondary flow in these gaps is an interesting feature of the paper. The authors conclude that gravity modulation has a stabilizing effect on secondary flow as compared to the case of constant gravitational acceleration. This effect diminishes with reduction in annulus radius ratio.