Magnetohydrodynamic convection in molten gallium

We present the results of an experimental and numerical study of the effect s of a steady magnetic field on sidewall convection in molten gallium. The magnetic held is applied in a direction which is orthogonal to the main how which reduces the convection and good agreement is found for the scaling o f this effect with the relevant parameters. Moreover, qualitatively similar changes in the structure of the bulk of the flow are observed in the exper iment and the numerical simulations. In particular, the how is restricted t o two dimensions by the magnetic held, but it remains different to that fou nd in two-dimensional free convection calculations. We also show that oscil lations found at even greater temperature gradients can be suppressed by th e magnetic field.