Instability of two superposed self gravitating viscous streams

Abstract EN

The instability of two superposed, semi-infinite, viscous, homogeneous and self-gravitating streams, separated by a horizontal interface z = 0, is investigated.

A dispersion relation is obtained in the most general case and a mathematically simple case of highly viscous fluids is dealt with.

It is found that the instability sets in for wavenumbers lying outside the region bounded between a circle and an ellipse in the first quadrant in the kx, ky plane for streams having the same fluid properties and moving in opposite directions with equal velocities.

The effect of kinematic viscosity on the growth rate of unstable configuration is found to have a dual effect.