Direct Simulation Monte Carlo Module

Description

DSMCM is based on DSMC(Direct Simulation Monte Carlo) method which is a probabilistic method to solve Boltzmann equation in gas theory. DSMCM is a module to compute the flow field of rarefied gas in various vacuum chambers. This module is applied to from viscous flow field to free molecule flow field by using the new collision method(U-system)[1][2]. The new collision method has been implemented to DSMCM. There are no restriction of mesh width depending on mean free path length by using this method. And test particle Monte Carlo method is used to compute rapidly the flow field of gas of which neutral density such as radicals or sputtered particles is very low compared with fed gas.

[1] Usami, M. and Nakayama T., Intermolecular Collision Scheme of DSMC Taking Molecular Locations within a Cell into Account, Rarefied Gas Dynamics, AIP Conference Proceedings, Vol.663 (2003), pp.374-381.

[2] Usami, M. and Mizuguchi, K., DSMC Calculation of Vortex Shedding behind a Flat Plate with a New Intermolecular Collision Scheme, Rarefied Gas Dynamics, AIP Conference Proceedings, Vol.762 (2005), pp.686-691.

Input data

• Specify computational domain, flow-in, flow-out and obstacles defined by two-dimen sional rectangular mesh system in Cartesian or cylindrical (axial symmetry model) coordinates.
• Specify the following boundary conditions for flow-in for each species.
  • Distribution of flow-in velocity
  • Distribution of mass flux
  • Distribution of temperature

Output data

• Spatial distributions of density, pressure, temperature and flow-velocity for each species.
• Particle and energy fluxes of each species on the targets and walls.

Example

• Benard flow
• Crossing flow of vertical board
• Taylor-Couette flow
• Flow field of wing edge
• Analysis of a Magnetron Sputtering Equipment
• Self-ionized sputtering
• Sputtering particle transfer in a DC magnetron sputtering equipment
• Flow field (Specular reflection)
• Flow field (diffuse reflection)