Based on two-dimensional Euler equations

and in combination with the high-resolution hybrid Roe/HLL (Harten-Lax-Van Leer) scheme and adaptive mesh refinement method

numerical simulations of single ejection driven by two pulse detonation engines (PDE) were performed.The results show the propagation processes of the ejection of the primary detonation and the secondary detonation induced inside the ejector.After two detonation waves are ejected out

they propagate in the form of unexpanded jet flow

and interact with each other at the same time

postponing the ejection time of the exhausted gases and decreasing the absorption time of ambient air.As a result

the ejection efficiency of the ejector decreases

and the numerical results agree well with corresponding experimental results.