Surface effects in rarefied gas dynamics: an analysis based on the Cercignani–Lampis boundary condition

The flow of a rarefied gas, in a plane channel, is investigated, with special attention to the gas–surface interaction, modeled by the Cercignani–Lampis kernel that is defined in terms of normal and tangential accommodation coefficients. An analytical version of the discrete-ordinates method is used to solve, in an unified approach, the Poiseuille flow, thermal-creep flow and Couette flow problems with kinetic equations defined in terms of the BGK model. Numerical results for the velocity and heat-flow profiles and flow rates are reported, for a wide range of the accommodation coefficients and the Knudsen number.