Investigating Rotating Detonation Mode Fueled by Precombustion Cracking Gas

To reduce the requirement of rotating detonation related to the temperature of the incoming air, this study develops a rotating detonation combustor with precombustion cracking. Stable detonation was carried out without an oxygen supplement at a temperature of the incoming air of 419 K, and the technical advantage of using precombustion cracking to activate kerosene was verified. Cross-correlation analysis and high-speed image diagnosis were then used to analyze the mode of the detonation wave. The results show that the mode was a double-wave collision, and the speed of propagation of two opposing waves was different such that it led to the movement of the points of collision. The results of the cross-correlation analysis were used to determine the trajectory of these points. High-speed image-based mode recognition was used to directly observe the processes of conversion of the single-wave and double-wave modes of collision, where the velocity of the wave was 900 m/s as determined by the time–space diagram. The effect of the number of injection holes on the boundary of detonation was also examined. We found that the boundary of detonation shifted to lean with a decreasing number of injection holes.