DEVELOPMENT OF A RAREFIELD GAS-FLOW SIMULATOR USING THE DIRECT-SIMULATION MONTE-CARLO METHOD - 2-D FLOW-ANALYSIS WITH THE PRESSURE CONDITIONS GIVEN AT THE UPSTREAM AND DOWNSTREAM BOUNDARIES

A simulation program for rarefied gas flow with the pressure conditions given at the upstream and downstream boundaries has been developed. With the pressure conditions given at the upstream and downstream boundaries, flow velocities at these boundaries are revised in every time step according to the number of molecules going in and out. Thus, a steady solution for the continuous flow properties at the upstream and downstream boundaries is obtained by averaging the flow properties after a certain time. The algorithm of molecular movements and collisions is based on the direct simulation Monte Carlo method by Bird. Results of the calculation by this program are compared with and verified by Dong's empirical results for a 2-D Poiseuille flow.