Models and Correlations for Rarefied Gas Flows in Polygonal and Trapezoidal Microducts

Abstract

Predictive models are developed for reduced flow rates and Poiseuille numbers for rarefied gas flows in long regular polygonal (circle, square, equilateral triangle) and isosceles trapezoidal microducts for all Knudsen numbers. Correlations are obtained for free molecule reduced flow rates and continuum Poiseuille numbers for regular polygons in terms of the number of sides. Models and accurate correlations are proposed for a new parameter defined as the ratio of the reduced flow rate for arbitrary rarefaction to the reduced flow rate corresponding to the maximum rarefaction parameter. The correlations are applicable for all Knudsen numbers.