Research in DSMC

1. Research in DSMC • Development of a general-purpose 2D/2D-axisymmetric/3D [Parallelized Direct Simulation Monte Carlo Code (PDSC)] • Solving the Boltzmann equation using particle-based Monte Carlo method • < 5 sets in the world (DAC & MONACO in USA; SMILE in Russia) • Unstructured grid topology that is flexible in treating complex geometry. • Dynamic domain decomposition & variable time step scheme that greatly increases the computational speed. • Parallelized adaptive mesh refinement that improves solution accuracy where it needs. • Developing extended conservative weighting scheme in efficiently treating flow problems involving trace species. • Development of pressure-boundary treatment method for internal flow problems. • Deriving VSS collision parameters using quantum chemistry calculation. • Developing non-equilibrium high-temperature chemistry module related to air • Developinghybrid DSMC-NS scheme • Applications include micro gas flow, vacuum technology, plume impingement in space vehicle, hypersonic non-equilibrium aerodynamics, PVD process, etc.

2. Research in DSMC (cont’d) Dynamic domain decomposition (64 processors) Parallel Adaptive Mesh Refinement Hypersonic flow past the Apollo (with chemical reactions) Hybrid DSMC-NS scheme (nozzle plume) Plume impingement on spacecraft (Formosan-3) Spiral-grooved pump flow Sputtering PVD flow (neutral species) Under-expanded twin-jet interaction