A Study on the Pumping Performance of a Disk-type Drag Pump

Title & Authors
A Study on the Pumping Performance of a Disk-type Drag Pump
Hwang, Young-Kyu; Heo, Joong-Sik; Choi, Wook-Jin;

Abstract
Numerical and experimental investigations are performed for the molecular transition and slip flows in pumping channels of a disk-type drag pump. The flow occurring in the pumping channel develops from the molecular transition to the slip flow traveling downstream. Two different numerical methods are used in this analysis: the first one is a continuum approach in solving the Navier-Stokes equations with slip boundary conditions, and the second one is a stochastic approach through the use of the direct simulation Monte Carlo method. In the experimental study, the inlet pressures are measured for various outlet pressures in the range of 0.1$\small{{\sim}}$4Torr. From the present study, the numerical results of predicting the performance, obtained by both methods, agree well with the experimental data for the range of Knudsen number $\small{Kn{\leq}0.1}$ (i.e., the slip flow regime). But the results from the second method only agree with the experimental data for Kn>0.1(i.e., the molecular transition regime)
Keywords
Disk-type Drag Pump;Direct Simulation Monte Carlo Method;Molecular Transition Region;Compression Ratio;Throughput;
Language
Korean
Cited by
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