Abstract
In the present paper, jet impingements of gas expanded through an orifice into a vacuum were numerically simulated by using the direct simulation Monte Carlo (DSMC) method. Three types of jet impingement, parallel, oblique and normal, were treated. The parallel and oblique impingements were considered as a three-dimensional problem, whereas normal impingement was treated as an axisymmetric problem. The numerical simulations were carried out using the variable soft sphere (VSS) model for nitrogen. For the energy exchange between translational and rotational modes, the Borgnakke-Larsen model was employed together with the temperature-dependent energy exchange probability of Boyd. Simulated results were compared with Legge’s experiments and a simple impingement model in the range of the reservoir pressures from 0.1×104 to 1.6×104 Pa. The present results agreed well with Legge’s experimental data of pressure and shear stress distributions on a flat plate.
