Wish upon a star - Fluid instabilities due to mass outflow from sources
by
Larry Forbes
University of Tasmania

Imagine a source of mass in a fluid, injecting fluid of a different density into its surroundings. This creates an interface between the two fluids, that moves outwards in some fashion as time increases. If the fluid from the source is lighter than the surrounding fluid, the interface between them is unstable, and disturbances to it will grow with time. This is then a type of Rayleigh-Taylor instability in non-planar geometry, and could be generated in laboratory experiments, or might even explain some of the elaborate fingering-type structures seen in astrophysical data.

This talk will consider outflow from a line source, possibly with the inclusion of an inwardly-directed gravitational force to allow for astrophysical simulations. An inviscid theory will be presented, and the possibility of curvature singularities at the interface will be discussed in the context of that theory. Viscous effects will then be accounted for, and reveal that intriguing radial plume structures can be created, with over-turning interfaces.

Date received: December 17, 2009