The starting transient in a gas-generator hybrid rocket motor

A model for the prediction of the starting transient in a gas-generator hybrid motor is presented. The model considers essential design parameters such as complex grain configuration, boundary conditions, erosive burning rate, as well as spatially and temporally variable thermodynamic properties of both condensed material and gas flow. The developed numerical code for the model solution demonstrates a strong capability for solving time-dependent fluid dynamics problems and can be particularly useful for internal ballistics considerations as well as for stability analysis. Several scenarios for starting transients of a large-size motor are considered and worst case events are identified.