Journal of computational fluids engineering (한국전산유체공학회지)

Korean Society of Computational Fluids Engineering (한국전산유체공학회)
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EFFECTS OF THE REYNOLDS AND KNUDSEN NUMBERS ON THE FLOW OF A MICRO-VISCOUS PUMP

Reynolds 수와 Knudsen 수가 초소형 점성펌프에 미치는 영향

  • Published : 2008.06.30
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Abstract

Effects of the Reynolds and Knudsen numbers on a micro-viscous pump are studied by using a Navier-Stokes code based on a finite volume method. The micro viscous pump consists of a circular rotor and a two-dimensional channel. The channel walls are treated by using a slip velocity model. The Reynolds number is studied in the range of $0.1{\sim}50$. The Knudsen number varies from 0.01 to 0.1. Numerical solutions show that the pump works efficiently when two counter rotating vortices formed on both sides of the rotor have the same size and intensity. As the Reynolds number increases, the size and intensity of the vortex on the inlet side of the pump decrease. It disappears when the Reynolds number is larger than about Re=20. The characteristics of the performance of the pump is shown to deteriorate, in terms of mean velocity and pressure rise, as the Reynolds number increases. The Knudsen number shows a different effect on the characteristics of the pump. As it increases, the mean velocity and pressure rise decrease but the characteristics of the vortex flow remains unchanged, unlike the effect of Reynolds number.

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References

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