Similarities of rarefied gas flows in elliptical and rectangular microducts

Abstract Models and corresponding correlations are given for rarefied gas flows in long elliptical and rectangular microducts for all Knudsen numbers. These models are based on reduced flow rates which are scaled with the square root of the area. Correlations are given for two limits: free molecule flow and for continuum flow. Two new dimensionless flow parameters are introduced. The first one is based on the normalized flow rate and the second one is based on the product of the reduced flow rate and the continuum Poiseuille number. Slip flow models are given for the elliptical and rectangular cross sections.