Gas–surface interaction impact on heat transfer and pressure distributions of a high speed microchannel flow

The present work performs a computational study of a supersonic flow in a two-parallel-plates microchannel. Effects of incomplete surface accommodation on the surface properties of the microchannel were investigated by employing the Direct Simulation Monte Carlo (DSMC) method in combination with the Cercignani–Lampis–Lord (CLL) gas–surface interaction model. The work focuses the attention on the heat flux, pressure, and shear stress distributions on the parallel-plate surfaces due to differences in the accommodation coefficients of the lower and upper surfaces of the microchannel. It was found that accommodation coefficients have different influence on heat transfer, pressure and skin friction coefficients for the conditions investigated. The analysis showed that changes on the accommodation coefficients of the upper surface affected the wall pressure and the heat flux to the lower surface.