Thermal Gradient Driven Flow

A thermal creep process is studied in a wide rectangular micro channel considered as two infinite parallel plates. The inlet and outlet reservoirs are kept at the same constant pressure. A constant temperature gradient exists along the walls of the channel joining the two tanks. Thus a gas flow is induced and thermally sustained until steady conditions are reached. A complete steady analytical solution is derived in slip regime for Knudsen numbers smaller than 0.25. The analytical results are in good agreement with the numerical “exact” solution of the continuum equations system. Furthermore our continuum approach results are compared to those deduced from the approaches based on the Boltzmann equation model treatments: these various methods lead generally to a satisfactory agreement between their respective mean parameters. Nevertheless significant differences appear on the transversal velocity profiles in the close vicinity of the wall.