Abstract. Mathematical modeling of gas-dynamic processes in a model solid rocket motor (SRM) chamber for the entire combustion period of an axisymmetric case-bonded solid propellant grain is presented. The mathematical formulation is described by the mass, momentum, and energy conservation equations for an ideal gas in an axisymmetric approximation. The numerical solution was obtained using the Godunov method on a computational mesh accounting for the grain shape and nozzle section. An algorithm to reduce the computation time for gas dynamics in the SRM chamber over the entire combustion period is presented. The algorithm assumes quasi-steady behavior of the grain burning rate over a time interval much shorter than the total grain burning time and much greater than the time step of the numerical scheme. To accelerate convergence to a steady state in the chamber after each grain geometry change during combustion, the mean pressure was specified using the steady-state pressure equation (Bory’s formula). The gas dynamics are calculated until steady flow is established in the SRM chamber. Gas-dynamic processes in the chamber of a model SRM were simulated for the entire combustion period of an axisymmetric case-bonded solid propellant grain of two configurations: with a gap between the case head end and the grain, and with an umbrella-shaped grain. The time dependencies of the mean pressure in the combustion chamber over the grain burning period were obtained.

Keywords: combustion chamber, gas dynamics, grain combustion, numerical simulation, solid propellant

For citation: Krainov A. Yu., Minkov L. L., Moiseeva K. M. Simulation of solid propellant combustion product flow in a model solid rocket motor chamber over the full operating period. Aerospace Engineering and Technology. 2026. Vol. 4, no. 1, pp. 66–74. (In Russ.) https://doi.org/10.52467/2949-401X-2026-4-1-66-74; https://elibrary.ru/GRGDMZ

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