Molecular flow transmission probabilities of any regular polygon tubes

Research on the molecular flow transmission probabilities of tubes is important in vacuum science and technology, as well as in some special applications in space technology. This study examines an algorithm based on Monte Carlo method to calculate the molecular flow transmission probabilities of any regular polygon tubes. This method fully utilizes the symmetries of regular polygons to simplify calculation. The results show that when the cross-sectional areas and lengths L of tubes remain constant, the molecular flow transmission probabilities of regular polygon tubes increase and approach those of cylindrical tubes with an increase in the number of sides. Moreover, any regular polygonal or cylindrical cross-section tube has nearly the same transmission probability within 2.8% of the maximum difference in the range of L ≤ 100 (the cross-sectional area of each tube is π).

► Molecular flow rates of regular polygon tubes are calculated with a MC method.
► The symmetries of tubes are fully utilized, so the calculation process is simplified.
► Molecular flow rates of polygon tubes are almost irrelevant to the number of sides.