Boundary conditions for gases on a body surface

The influence of boundary conditions on the distribution of macroscopic parameters of various types is studied using the problem of heat transfer for monatomic and diatomic gases as an example. The calculations are made on the basis of model kinetic equations [1, 2]. A boundary condition that takes into account mutual transitions of rotational and translational energies of particles when they collide with a body surface is proposed for diatomic gas. Comparison with the experimental results made it possible to determine the coefficients appearing in the boundary conditions.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 141–148, September–October, 1986.