Virtual Solid Cell Model for Mimicking Porous Media in Rarefied Gas Flow Analysis Based on Direct Simulation Monte Carlo Method

Abstract

In this paper, I propose a new model named virtual solid cell (VSC) to treat porous media more simply in the Direct Simulation Monte Carlo method. The conventional random solid cell (RSC) model represents porous media by randomly arranging solid cells in a fluid domain. In contrast, the VSC model basically treats porous media as a fluid domain, but it produces the same effect as the RSC model by imposing a stochastic limit corresponding to the porosity on the inter-cell transfer of molecules. Due to its advantage as a stochastic method, the VSC model enables one-dimensional simulation of rarefied gas flow passing through porous media, contributing to a significant reduction in computation time. It also facilitates the treatment of complex porous media with various porosities. Furthermore, the VSC model shows its potential as a new boundary model to describe surface roughness and conditions.