A dusty gas model-direct simulation Monte Carlo algorithm to simulate flow in micro-porous media

Abstract

A new efficient direct simulation Monte Carlo -DSMC- method is proposed for the simulation of micro-porous media based on the dusty gas model. Instead of simulating gas flow through a micro-porous medium with a complex geometry of micro-pores that mimics the physical pore morphology, the dusty gas model-direct simulation Monte Carlo -DGM-DSMC- method replaces it with the gas flow through a system of randomly distributed motionless virtual particles with simple spherical shapes confined in the considered domain. In addition, the interactions of gas molecules with the porous particles are simulated stochastically. For the aim of our study, the dusty gas model is implemented in Bird\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\'s two-dimensional DSMC code. The obtained results for the average velocity of gas flow through microscale porous media with given porosity are verified for different pressure gradients with those reported in the literature where porous particles are modeled physically in the domain. Thereafter, the effective parameters in porous media such as porosity, particles diameter, and rarefaction on flow behavior including velocity profile, apparent gas permeability, and mass flow rate are investigated. A comparison with the results predicted by the Open source Field Operation And Manipulation -OpenFOAM- software suggests that the employed DGM-DSMC is more accurate in highly porous media and its computational cost is considerably low.