Theoretical study on the impact of azimuthal parameter variations on the performance of a rotating detonation engine

This study analyzes the total pressure variation in rotating detonation engines (RDEs) from a theoretical modeling perspective. Zero-dimensional analysis of the rotating detonation wave was first carried out. It was found that the total pressure gain in the rotating detonation combustor originates from the choice of the coordinate system: when observed in the ground-fixed coordinate system, the motion of the detonation wave results in higher total pressure in the gases behind the wave, while no total pressure gain is observed in the wave-fixed coordinate system. Subsequently, a one-dimensional model based on the Taylor wave was developed to describe the variation of azimuthal parameters behind the detonation wave, enabling the evaluation of total pressure gain at both the triple-point cross section and the combustor outlet. Two-dimensional numerical simulations of the RDE were conducted to validate the theoretical model, which demonstrated reasonable accuracy within the operating range considered in this study. Finally, the total pressure change throughout the RDE system was quantitatively examined. The results indicate that whether the system achieves a total pressure gain depends on the relative magnitude of the losses upstream and downstream of the detonation wave compared to the gain produced by the detonation.