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http://dx.doi.org/10.9725/kstle-2012.28.5.218

A Comparative Study of the Navier-Stokes Equation & the Reynolds Equation in Spool Valve Analysis  

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)
Publication Information
Tribology and Lubricants / v.28, no.5, 2012 , pp. 218-232 More about this Journal
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.
Keywords
spool valve; validity; Navier-Stokes equation; Reynolds equation; lateral force; volume flow rate; friction force;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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