Numerical Simulation of the Flow Field in Scramjet with Different Structure Combustion

The flow fields in scramjet with different length depth ratio(L/D) cavities(combustion)were simulated numerically in cold by using two steps up-wind NND scheme for Euler equations.Shock could be catch and analyzed trait clearly,the trait of flow field and vortex could be imaged clearly;The conclusions are as follows:the low velocity、high pressure and vortex area were obtained with cavity to mix fuel and burn.Cavity length depth ratio strongly influences flow field、total pressure recovery、drag coefficient.the bigger the ratio of length to depth is,the stronger the vortex is,the bigger the total pressure loss is,the bigger the drag is.