(A) stochastic particle Fokker-Planck method for multiscale rarefied gas flows

Abstract

The dissertation addresses the stochastic particle Fokker-Planck (FP) method for rarefied gas flows. Focusing on extending the capability of the FP method for practical engineering applications, various topics are covered in the dissertation. First, the dissertation presents several numerical results for rarefied gas flows using DSMC and FP methods. These results help to better understand the limitations and potential of the FP method for rarefied gas flows. Second, new FP models are devised to describe diatomic gases and gas mixtures. It is demonstrated that the new FP models show reasonable agreement with the DSMC method near equilibrium. Third, a new particle integration scheme is introduced to improve the computational efficiency of the FP method. It is observed that the new integration scheme provides better convergence behavior for cell size and time step than the DSMC method. Finally, the hybrid FP-DSMC approach is studied for efficient simulation of multiscale rarefied gas flows.