Unsteady simulation and experimental study of hydrogen peroxide throttleable catalyst hybrid rocket motor

In this paper, a series of simulations and experiments about hydrogen peroxide throttleable catalyst hybrid rocket motor were conducted during thrust regulation process. Some characteristics of this motor were investigated such as regression rate, pressure in chamber and thrust. The motor used polyethylene (PE) as the solid fuel and 90% hydrogen peroxide (H2O2) as the oxidizer. To investigate transient process of this throttleable motor, an unsteady simulation model was developed. The realizable k-ε turbulence model combined with the Eddy-Dissipation combustion model was applied in this paper, and gas-solid coupling model was used to simulate the regression process on the solid fuel surface. The distributions of temperature, pressure and solid fuel regression rate were obtained. A series of tests were conducted to verify the accuracy of the simulation model. From the comparison of the pressure in chamber between the simulation and test, the maximum error is 9%. The numerical model could predict the characteristics of this motor. The simulation results and the experimental data indicate that the chamber pressure and fuel regression rate cannot response to the oxidizer mass flow rate change immediately, it requires a lag time to readjust to new equilibrium.