Erosive burning of a solid propellant in a supersonic flow

We present results of an experimental study of burning of a ballistite solid propellant (gun powder H) in a supersonic flow. It is shown that the criterial dependence of the erosion coefficient on the Vilyunov parameter obtained on the basis of experimental results in a subsonic and a supersonic flow describes satisfactorily experimental data for a supersonic flow in the examined range of Mach numbers $\mathrm{M} = 1-2.8$ as well. A more correct approximation formula for the range of parameters considered is derived. The specific features of the flow along the surface of a solid propellant at $\mathrm{M}>1$ is analyzed, and this analysis has revealed some problems in the interpretation of experimental data.