A model is developed for rarefied gas flow in long microtubes with different inlet-outlet pressure ratios at low Mach numbers. The model accounts for significant changes in Knudsen number along the length of the tube and is therefore applicable to gas flow in long tubes encountering different flow regimes along the flow length. Predictions from the model show good agreement with experimental measurements of mass flow rate, pressure drop, and inferred streamwise pressure distribution obtained under different flow conditions and offer a better match with experiments than do those from a conventional slip flow model.

Date of this Version


Published in:

Z. Yang and S.V. Garimella, "Rarefied Gas Flow in Microtubes at Different Inlet-Outlet Pressure Ratios," Physics of Fluids, Vol. 21, 052005 (15 pp), 2009.