Optimization method for primary rocket mass flow rate in rocket ejector mode

Optimization method of primary rocket mass flow rate was studied for rocket based combined cycle(RBCC) in rocket ejector mode, and the mass flow rate variation investigated along the flight trajectory. An optimization model for primary rocket mass flow rate was proposed by adopting the effective specific impulse as the single optimization objective in rocket ejector mode. The proportion-control method was established for solving secondary fule mass flow rate, which matches the primary rocket mass flow rate. Based on the experiment design and genetic algorithm methodology, optimization method for primary rocket mass flow rate in rocket ejector mode was established in considering the couple relationship between performance optimization and trajectory simulation. Optimization of primary rocket mass flow rate in rocket ejector mode was investigated for air-launching RBCC vehicle to provide the variable mass flow rate in the flight operation. It shows that the primary rocket mass flow rate reaches the peak for overcoming the sound barrier, which brings about much higher design requirement for thrust; The primary rocket mass flow rate begins to throttle for the domination of ram effect over ejection effect, which brings about much higher design requirement for specific impulse; the primary rocket maintains a low level of mass flow rate for stable operation above Ma=1.5. The regulating ratio of primary rocket mass flow rate reaches 5.0 in rocket ejector mode.