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http://dx.doi.org/10.3795/KSME-B.2003.27.7.948

The Effect of Rotation of Discharge Hole on the Discharge Coefficient and Pressure Coefficient  

Ha, Kyoung-Pyo (현대자동차 파워트레인연구소)
Ku, Nam-Hee (서울대학교 대학원 기계공학과)
Kauh, S.Ken (서울대학교 기계공학과)
Publication Information
Transactions of the Korean Society of Mechanical Engineers B / v.27, no.7, 2003 , pp. 948-955 More about this Journal
Abstract
Pressure coefficient in rotating discharge hole was measured to gain insight into the influence of rotation to the discharge characteristics of rotating discharge hole. Pressure measurements were done by the telemetry system that had been developed by the authors. The telemetry system measures static pressure using piezoresistive pressure sensors. Pressure coefficients in rotating discharge hole were measured in longitudinal direction and circumferential direction with various rotating speed and 3 pressure ratios. From the results, the pressure coefficient, and therefore the discharge coefficient, is known to decrease with the increase of Ro number owing to the increase of flow approaching angle to the discharge hole inlet. However, there exists critical Ro number where the decrease rate of discharge coefficient with the increase of Ro number changes abruptly; flow separation occurs from the discharge hole exit at this critical Ro number. Critical Ro number increases with the increase of length-to-diameter ratio, but the increase is small where the length-to-diameter ratio is higher than 3. The decrease rate of discharge coefficient with the increase of Ro number depends on the pressure recovery at the discharge hole, and the rate is different from each length-to-diameter ratio; it has tendency that the short discharge hole shows higher decrease rate of discharge coefficient.
Keywords
Rotating Discharge Hole; Rotation Effect; Discharge Coefficient; Pressure Coefficient; Telemetry;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
연도 인용수 순위
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