Parametric studies of the thermal and momentum accommodation of monoatomic and diatomic gases on solid surfaces

Abstract

The thermal accommodation coefficient (TAC) and the momentum accommodation coefficient (MAC) are the two fundamental parameters quantifying the solid–gas energy and momentum exchange efficiencies. We use molecular dynamics (MD) simulations to study the effect of individual interfacial parameters including, (i) solid–gas interaction strength, (ii) gas–solid atomic mass ratio, (iii) solid elastic stiffness, and (iv) temperature, on TAC and MAC at solid surfaces in contact with monoatomic and diatomic gases. In addition to offering a fundamental understanding on how these individual parameters affect the nature of gas–solid collisions, we provide an extensive database for the TAC and MAC. We also study the effect of surface functionalization with molecular monolayers on the energy and momentum transfer at the interface. These results are useful in developing interfaces with enhanced heat transfer under various operation conditions.