Numerical research on kerosene/hydrogen/air rotating detonation engines with discrete injection strategies

Abstract

The two-dimensional simulation of two-phase rotating detonation engines commonly adopts the nozzle–wall configuration, which is inconsistent with the real configurations in experiments. In the annular slot–nozzle structure, the oxidant is completely injected into the annular gap, whereas the fuel is partially injected into the nozzle hole, which is closer to the real operation condition. In this study, a gas–liquid two-dimensional numerical investigation was conducted to explore a more accurate operating condition with a discrete injection configuration. The effects of the kerosene/hydrogen injection area ratio and hydrogen equivalence ratio on the propagation mode and operating performance were investigated. The simulation results show that the kerosene droplet/hydrogen/air gas–liquid two-phase rotating detonation wave exhibits different propagation modes depending on the hydrogen equivalence ratio. When the hydrogen equivalence ratio (φH2) is 0, the detonation wave cannot be successfully initiated. When φH2 is increased to 0.2 and 0.5, a single-wave propagation mode is generated. When φH2 is 1, a double-wave propagation mode is produced initially in the combustion chamber and is subsequently converted into the deflagration mode. The flow field structure, velocity performance, and propulsive performance in the detonation combustion chamber are analyzed. It was found that an appropriate amount of hydrogen addition to the liquid kerosene detonation can aid in stabilizing the propagation of the detonation wave and improving the performance of the detonation engine.