Hao YAN, Xin HAN, Haochen XIONG, Chongguang SHI, Yancheng YOU
DOI Number: XXX-YYY-ZZZ
Conference Number: HiSST-2024-0036
This study investigates the impact of curvature on the reflection of detonation waves in a detonation engine. The reflection of detonation waves in the combustion chamber is inevitable and therefore requires investigation. This paper focuses on the reflection of curved detonation waves on convex and concave walls, and the reflection can be either Mach or regular reflection by changing the curvature of the wall. It has been determined that there are two mechanisms by which curvature affects the stability of the waves: firstly, curvature affects the angle of the wave, leading to the appearance of a subsonic and high-temperature/high-pressure region behind the wave, which affects stability; secondly, curvature affects the mutual positioning of the wave systems, leading to mutual interference and stability. Based on the numerical results, a theoretical criterion for predicting the stability of detonation wave reflection has been proposed. This criterion quantifies the difference between the stability of the reflected wave and the actual reflected wave state, and when this difference is small, the reflected wave is stable; when this difference is large, the reflected wave is unstable. The rationality of this criterion has been demonstrated by comparing different simulation results and wave system structures at different times. With the help of this criterion, the main factors affecting the stability of detonation wave reflection have been analysed, providing a reference for detonation engine design. In addition, analysis of the detonation wave flow field has revealed the important influence of curvature. Therefore, a relationship between the gradient of wave parameters and curvature has been established, which can be used for detonation reflection analysis and generally regulate gradient effects of curved walls. Comparison with simulation results shows that this relationship can effectively predict the gradient of the reflected wave and provide a higher-order analysis tool for detonation reflection.