Experimental study on detonation characteristics of a reverse-flow pulse detonation combustor with different operating parameters

Pulse detonation can achieve pressure gain through the combustion process, significantly improving the thermal efficiency and overall performance of power systems. In order to investigate the influence of operating parameters on the detonation characteristics of a reverse-flow pulse detonation combustor (PDC), experiments were conducted to analyze and compare the effects of different inlet total temperatures, total pressures, equivalence ratios, and operating frequencies on the pressure distribution and wave speed variations along the flow path, and stable working characteristics. The results show that the deflagration to detonation transition (DDT) distance of the reverse-flow PDC decreases with increasing total inlet total temperature and pressure, but tends to stabilize when the inlet total temperature exceeds 423 K. The studied reverse-flow PDC has an optimal equivalence ratio range of 1.0–1.2 across all operating conditions. Under inlet total pressure of 0.15 MPa and total temperature of 323 K condition, the optimal equivalence ratio is around 1.2, while under inlet total pressure of 0.42 MPa and total temperature of 465 K condition, the optimal equivalence ratio is near 1. The DDT distance initially decreases and then increases with frequency. Under inlet total pressure of 0.15 MPa and total temperature of 323 K condition, the optimal frequency is 15 Hz.