Derivation of generalized Maxwell velocity slip model

Based on the conservation of momentum and energy fluxes in the Knudsen layer, a generalized Maxwell velocity slip boundary model is derived in detail using the velocity distribution function from the Grad thirteen moment approximation. The study shows that the generalized Maxwell velocity slip boundary model has the same form as the slip model Oven by Lockerby. In addition, it is consistent with the typical Maxwell velocity slip model when the temperature gradient along the surface and the normal velocity of gas flow are neglected.