Applicability conditions for inverse methods of reconstructing the nonsteady burning rate

Applicability conditions for inverse methods of reconstructing the time-dependent burning rate of solid fuels are analyzed by studying the effect of the varying burning rate on the pressure in the combustion chamber. Thermodynamic and one-dimensional gas-dynamic approximations are considered. It is shown that the thermodynamic statement of the inverse problem can be used to study processes with characteristic times longer than 0.2 of the combustion-chamber free-volume relaxation time. Making allowance for one-dimensional effects is feasible and appropriate where experimental data on butt-end burning of readily combustible fuels are treated.