Tribology and Lubricants

Korean Tribology Society (한국트라이볼로지학회)
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A Comparative Study of the Navier-Stokes Equation & the Reynolds Equation in Spool Valve Analysis

스풀밸브 해석에서 Navier-Stokes 방정식과 Reynolds 방정식에 의한 비교 연구

  • Hong, Sung-Ho (School of Mechanical, Aerospace & Systems Engineering, KAIST) ;
  • Son, Sang-Ik (School of Mechanical, Aerospace & Systems Engineering, KAIST) ;
  • Kim, Kyung-Woong (School of Mechanical, Aerospace & Systems Engineering, KAIST)
  • 홍성호 (KAIST 기계항공시스템학부) ;
  • 손상익 (KAIST 기계항공시스템학부) ;
  • 김경웅 (KAIST 기계항공시스템학부)
  • Received : 2012.05.28
  • Accepted : 2012.07.05
  • Published : 2012.10.31
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Abstract

In a spool valve analysis, the Reynolds equation is commonly used to investigate the lubrication characteristics. However, the validity of the Reynolds equation is questionable in a spool valve analysis because cavitation often occurs in the groove and the depth of the groove is much higher than the clearance in most cases. Therefore, the validity of the Reynolds equation in a spool valve analysis is investigated by comparing the results obtained from the Reynolds equation and the Navier-Stokes equation. Dimensionless parameters are determined from a nondimensional form of the governing equations. The differences between the lateral force, friction force, and volume flow rate (leakage) obtained by the Reynolds equation and those obtained by the Navier-Stokes equation are discussed. It is shown that there is little difference (less than 10%), except in the case of a spool valve with many grooves where no cavitation occurs in the grooves. In most cases, the Reynolds equation is effective for a spool valve analysis under a no cavitation condition.

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References

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Cited by

  1. Comparative Study of the Navier-Stokes Equation & the Reynolds Equation in Spool Valve Analysis Considering Cavitation vol.29, pp.5, 2013, https://doi.org/10.9725/kstle.2013.29.5.275
  2. Study on Lubrication Characteristics of Spool Valve with Various Cross-sectional Groove Shapes vol.29, pp.3, 2013, https://doi.org/10.9725/kstle-2013.29.3.149