Results are presented of a two-dimensional, time-dependent numerical simulation of the growth and steady-state structure of electrothermal waves. A Cs seeded Ar plasma is considered which is of infinite extent in the 'y' direction, and bounded at x = 0 and x = H by electrically insulating walls. To restrict the problem to a finite domain, periodic boundary conditions are imposed in the 'y' direction. Wave behaviour is investigated for values of the electron Hall parameter,/3, between 0 and 10.
It is found that the introduction of a small amplitude perturbation into a uniform, unstable plasma leads to a final steady-state structure which is independent of the spatial form of the perturbation. The structure moves, relative to the heavy particles, in the direction of the average current flow; and the final highly non-uniform state is characterized by greatly reduced values of the effective electrical conductivity and Hall parameter, ~ert and Pen. Plots are given of the averaged parameters for the final solutions as functions of the initial Hall parameter, and of the temporal development of these parameters.
The dependence of the instability behaviour on the load to effective plasma conductivities, -L/aem is found to be weak for
Finally, it is found that a radiative energy conduction mechanism of sufficient magnitude to inhibit the growth of short wave, large error, electrothermal modes must necessarily be included in the electron energy equation at large fl if final stationary states are to be achieved.