Scattering properties and scattering kernel based on the molecular dynamics analysis of gas-wall interaction

• Published in: Physics of fluids (1994) 2007-08, Vol.19 (8), p.087102-087102-9
• Main Authors: Yamamoto, Kyoji, Takeuchi, Hideki, Hyakutake, Toru
• Format: Article
• Language: English
• Subjects: Accommodation; Condensed matter: structure, mechanical and thermal properties; Exact sciences and technology; Fluid dynamics; Fundamental areas of phenomenology (including applications); Physics; Rarefied gas dynamics; Solid-fluid interfaces; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties)
• ISSN: 1070-6631; 1089-7666
• DOI: 10.1063/1.2770513

The scattering behaviors of nitrogen molecules reflected at a platinum surface are studied by the molecular dynamics method for the gas-surface interaction. The platinum surface is assumed to physically adsorb xenon molecules. Distributions of molecular velocities after reflection are obtained for the impinging molecules with specified velocities within a small range. The scattering distribution shows a bimodal behavior consisting of diffuse reflection and a distribution shifting to the velocity distribution of the impinging molecules. Comparison between the present scattering distribution and the Cercignani-Lampis-Lord scattering kernel shows large differences. A simple scattering kernel using a bimodal distribution is proposed assuming mutual independence of distributions in each velocity component and is compared favorably to the present scattering distribution. In addition, the scattering kernel of the rotational energy of the molecule is discussed.