Gas-Solid Interface Interactions Based on Molecular Dynamics Simulations

Abstract

Gas-solid interface interaction as the key point and difficult point of dilute gas flow, understanding the mechanism of it, to have a clearer understanding of the gas molecules in the solid near-wall surface motion law. This paper combines the molecular dynamics method and particle beam method to simulate the interaction between argon molecules and solid platinum wall surface, to study the scattering law after the collision between gas molecules and solid surface at different incidence angles and the mechanism of energy conversion between them, the results show that the tangential kinetic energy is lost after the collision between gas molecules and wall surface, while the change of normal kinetic energy is determined by the magnitude of the incident velocity; the incident velocity is small, the reflected tangential velocity distribution basically fits the Maxwell reflection distribution when the incident velocity reaches a high speed, and the reflected tangential velocity distribution appears head-and-shoulder or even bimodal distribution, which is helpful for future research on the tangential momentum adaptation coefficient of the scattering nucleus model.