It is well known that in a gas-filled duct or channel along which a temperature gradient is applied, a thermal creep flow is created. The performance of a new type of Knudsen pump, which only requires isothermal hot or cold walls and is consequently much easier to control than a classic pump with temperature gradient along a surface, has been investigated, using the direct simulation Monte Carlo (DSMC) method. The DSMC code used in the present work has been implemented in the OpenFOAM, i.e., dsmcFoam. We first compare our DSMC solutions for mass flow rate of temperature-driven flow with those of Boltzmann-Krook-Walender equation and Bhatnagar-Gross-Krook solutions. Then, we focus on rarefied gas flow between two parallel structured surfaces at different temperatures. The effects of flow rarefaction on the mass flow rate of the temperature driven flow is examined. Also the effect of geometric parameters have been studied and show if one applies diffuse reflection boundary condition the pump don’t work.

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