Study of the characteristics and combustion efficiency of liquid kerosene/oxygen-enriched air rotating detonation wave with different modes

In a liquid kerosene rotating detonation engine (RDE), detonation waves often exhibit different propagation modes. The propagation characteristics with different modes are worthy of further study. To further investigate the propagation characteristics, a series of experiments was conducted, and the flow field characteristics under different modes were comparatively studied using high-speed photography and pressure sensors. The modal features and mode change trends obtained in the experiments were simulated using numerical methods. Based on this, the combustion efficiencies of the different modes were quantitatively characterized. The results showed that with increasing propellant mass flux, the detonation wave gradually changes from the two-counter wave mode to the single-wave mode, and the interim mode is a hybrid mode. Compared with the two-counter wave mode, the velocity deficit of a single wave is smaller, and the reaction zone is more compact. Numerical simulations show that a higher proportion of fuel is consumed by more violent chemical reactions in the single-wave mode; that is, the combustion efficiency in the single-wave mode is higher than that in the two-wave mode. The results provide a reference for further understanding the liquid fuel detonation phenomenon and improving fuel combustion efficiency.