Numerical investigation of backpropagation of air-breathing pulse detonation engine

Using spark ignition model, the phenomenon of backpropagation of air-breathing pulse detonation engine was numerically investigated. The formation and propagation characteristics of the backpropagation phenomenon were obtained. The results showed that the backpropagation can be divided into two parts: the pressure and the hot gas. Both the backpropagation of pressure and that of hot gas were induced by the deflagration wave and the retonation wave. The retonation wave played a dominant role for the backpropagation. The hot gas covered a smaller region than the backpropagation pressure. The hot gas would stop traveling to the upstream inlet at a certain location owing to the effects of the expansion waves. The backpropagation pressure would keep traveling upstream and make the fluid in the inlet flow toward upstream. The magnitude of the backpropagation pressure decreased relatively slowly and an optimization design for the inlet should be performed.