NUMERICAL INVESTIGATION OF IMPINGING JETS IN RAREFIED CONDITION USING DSMC METHOD

In this study, the flow field of impinging jets in rarefied condition and high pressure ratios was investigated. Direct Simulation of Monte Carlo (DSMC) method was employed to find the flow field at two different Knudsen numbers (Kn) of 0.1 and 0.01. For each studied Knudsen number the effects of different nozzle-to-plate distances (L) are studied. For all cases a supersonic jet forms downstream of the nozzle. The results show that no shock occurs in the supersonic jet impinging on the plate in contrary to those in the continuum regime. The variations of molecular number density, axial velocity and Mach number on the center line were computed and discussed for two different Knudsen numbers. In general, in these conditions the gas expands from specified upstream condition to a lower background monotonically.