Propagation behaviors of kerosene-fueled rotating detonation wave with varied atomizer locations

Abstract

In this study, we tested a rotating detonation engine (RDE) fueled by liquid kerosene. A scheme of circumferential array atomization with an injection throat upstream of the annular combustor was used to realize the kerosene-fueled rotating detonation. The propagation characteristics of rotating detonation waves (RDWs) were analyzed by varying the distance between the pressure-swirl atomizers and the injection throat. The dynamic pressure signals and the visualized high-speed images were captured in the combustor. When the fuel atomizers were close to the injection throat, an unstable detonation mode appeared during the operation of the combustor. There was a periodical extinction and reinitiation of detonation waves in the combustor because the wave formed in the combustor could not propagate self-sustainably. In the fuel-lean tests, the rotating detonation degenerated to the combustion mode intermittently. Subsequently, unstable detonation was detected during the recovery stage from combustion to detonation mode. As the equivalence ratio increased, the rotating detonation process exhibited better continuity, but the duration of unstable detonation also increased. The continuity and stability of the rotating detonation process could be significantly improved by lengthening a certain distance between the atomizers and the injection throat. The experimental results indicated an optimal location of the fuel atomizers for stable operation, which could serve as a reference for the design of the injection structure of liquid-fueled RDEs.