Effect of the inlet spatial fluctuation on the gas–solid continuous rotating detonation flow field characteristics

Continuous rotating detonation engines have been extensively studied due to their high thermal efficiency. The utilization of solid particles as fuel can effectively reduce costs and enhance detonation performance. We have constructed a compressible gas–solid multimedium flow combustion numerical method, employing the double flux model coupled with fifth-order weighted essentially non-oscillatory and third-order total variation diminishing Runge–Kutta schemes to solve the unsteady multi-component chemical reaction Eulerian–Eulerian equations. Finite-rate methods and surface reaction models are used to simulate the combustion of gaseous mixtures and carbon particles. The effects of the inlet total pressure spatial fluctuations and particle diameter on the flow field characteristics of the continuous rotating detonation engine are investigated. The results indicate that changing the fluctuation period significantly affects the number, propagation direction, and intensity of gas–solid two-phase continuous rotating detonation waves (CRDW). The variation of fluctuation amplitude noticeably alters the combustion characteristics of the two-phase continuous rotating detonation wave, and excessively high amplitudes cannot form continuous rotating detonation waves. Introducing solid particles into fuel significantly mitigates the impact of inlet total pressure spatial fluctuation and promotes propagation stability on the detonation waves. Moreover, when solid particle diameters reach or exceed the micrometer scale, they contribute more favorably to generating a stable detonation flow field. However, excessive particle sizes result in a low surface reaction rate and inadequate contribution of heat released from particle combustion to the propagation of detonation waves.