Numerical Study of the Influence of Inlet Mass Flow Rate on Rotating Detonation Flow Field Characteristics and Pressure Gain Performance

A three-dimensional numerical study is performed to investigate the effect of inlet mass flow rate on flow field characteristics and pressure gain of rotating detonation combustor. The results show that the mass flow rate has an important effect on the behavior of the detonation wave. When the inlet mass flow rate is increased, the flow Mach number of inlet throat increases and flow develops to a close critical state. After ignition, two counter-rotating detonation waves will collide in the combustor and the number of collisions decreases with the increase of inlet mass flow rate. The strong wave eventually engulfs the weak wave and develops into a single-wave mode. When the inlet mass flow rate is reduced, the detonation wave velocity and refill height of premixed gas increase. Deflagration area of flow field reduces and the stability is improved. In addition, when the inlet mass flow rate is reduced, the total pressure loss caused by expansion wave decreases. The pressure gain and fuel-based specific impulse are increased. However, increasing the total pressure gain also improves the static pressure fluctuation ratio of inlet throat. The phenomenon of high-pressure feedback under small flow rate condition is also more prominent.