A slip model for micro/nano gas flows induced by body forces

TL;DR

This paper develops a new slip model for micro/nano gas flows influenced by body forces, incorporating a novel parameter, and validates it through molecular dynamics simulations.

Contribution

It introduces a modified slip model with a new parameter to better describe gas flows under body forces in micro/nano channels.

Findings

The model accurately predicts slip velocity in simulated flows.

The new parameter improves the fit to molecular dynamics data.

Validation confirms the model's applicability to helium gas flows.

Abstract

A slip model for gas flows in micro/nano-channels induced by external body forces is derived based on Maxwell's collision theory between gas molecules and the wall. The model modifies the relationship between slip velocity and velocity gradient at the walls by introducing a new parameter in addition to the classic Tangential Momentum Accommodation Coefficient. Three-dimensional Molecular Dynamics simulations of helium gas flows under uniform body force field between copper flat walls with different channel height are used to validate the model and to determine this new parameter.