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http://dx.doi.org/10.3795/KSME-B.2008.32.5.382

Analysis of Pumping Performance of a Helical Drag Pump Using the Diffusion Equation  

Heo, Joong-Sik (한국기기유화시험연구원)
Publication Information
Transactions of the Korean Society of Mechanical Engineers B / v.32, no.5, 2008 , pp. 382-391 More about this Journal
Abstract
A simple analytical model of rarefied channel flow is developed to predict the compression ratio in a helical drag pump. If the surface velocity is zero, the model reduces to a capillary leaks. Predictions of our model agree well with the Knudsen's data for capillary leaks in transition flow, in addition to giving a good account of the Knudsen minimum. Also, the present results are compared with experimental data, and good agreement is obtained over the entire pressure range from molecular to slip flow.
Keywords
Diffusion Equation; Compression Ratio; Diffusion Coefficient; Knudsen Minimum; Molecular Transition Region;
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