Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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Effect of Vertical Clearance Between a Rotor and Stater of a Disk-Type Drag Pump on the Performance

원판형 드래그펌프 회전자와 고정자 사이의 간극이 성능에 미치는 영향

  • 권명근 (성균관대학교 대학원 기계설계학과) ;
  • 황영규 (성균관대학교 기계공학부)
  • Published : 2004.12.01
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Abstract

The pumping characteristics of a single-stage disk-type drag pump (DTDP) are calculated for the variation of the vertical clearance between a rotor and stator by the three-dimensional direct simulation Monte Carlo (DSMC) method. The gas flow mainly belongs to the molecular transition flow region. Spiral channels of a DTDP are cut on the both the upper and lower sides of a rotating disk, but a stationary disk is planar. The interaction between molecules is described by the variable hard-sphere model. The no time counter method is used as a collision sampling technique. The vertical clearance has a significant effect on the pumping performance. Experiments are performed under the outlet pressure range of 0.4∼533 Pa. When the numerical results are compared with the experimental data, the numerical results agree well quantitatively

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References

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