Rarefied Gas Flow Over a Solid Surface with Adsorbates

The molecular dynamics study is applied for interaction of the gas molecule with the solid wall to analyse the flow of a rarefied gas between two wall. The wall consisting of Pt molecules is considered to be in a state of physical adsorbates. Two problems are considered : one is the flow problem and the other is the temperature problem. It is found that the tangential momentum accommodation coefficient is about 0.8 when the relative speed ratio of the two walls is unity, while it decreases with increasing Knudsen number when the relative wall speed ratio is 5.0. It shown that the temperature accommodation coefficient is about 0.85 at 300K wall, 0.75 at 450K wall, and 0.69 at 600K wall.