I. Hashim et Sk. Wilson, THE EFFECT OF A UNIFORM VERTICAL MAGNETIC-FIELD ON THE ONSET OF OSCILLATORY MARANGONI CONVECTION IN A HORIZONTAL LAYER OF CONDUCTING FLUID, Acta mechanica, 132(1-4), 1999, pp. 129-146
In this paper we use classical linear stability theory to undertake a
detailed investigation of the effect of a uniform vertical magnetic fi
eld on the onset of oscillatory thermocapillary-driven Marangoni conve
ction in a horizontal layer of quiescent, electrically conducting flui
d healed from below. For simplicity we restrict our attention to the s
implest case of a fluid layer with a non-deformable free surface and p
erfectly electrically conducting boundaries in which the onset of conv
ection is always steady in the absence of the magnetic field. The pres
ent numerical calculations show that the presence of the magnetic fiel
d can cause the preferred mode of instability to be oscillatory rather
than steady convection. Nevertheless, in all the cases investigated t
he effect of the magnetic field is always to stabilise the layer relat
ive to the case of no magnetic field.