RAYLEIGH-TAYLOR INSTABILITY OF STEADY ABLATION FRONTS - THE DISCONTINUITY MODEL REVISITED

A new model for the instability of a steady ablation front based on th e sharp boundary approximation is presented. It is shown that a self-c onsistent dispersion relation can be found in terms of the density jum p across the front. This is an unknown parameter that depends on the s tructure of the front and its determination requires the prescription of a characteristic length inherent to the instability process. With a n adequate choice of such a length, the model yields results, in excel lent agreement with the numerical calculations and with the sophistica ted self-consistent models recently reported in the literature. (C) 19 97 American Institute of Physics.