The starting process of the pulse combustion wind tunnel is unsteady and very complex.It couldn't be investigated by use of the experimental method in existence.In this paper

the starting process was simulated by the Fluent computational fluid dynamics(CFD) code.The current version of this code employs dual-time formulation

second order upwind interpolation scheme

shear stress transport(SST) k-ω turbulence model

and species transport equation.The transient flow structure during nozzle starting process and the establishing process of supersonic flow in the free jet region were analyzed.The results provide a reference for the improvement of the starting characteristics of the pulse combustion wind tunnel.