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Pressure Drop Distributions in Rotating Channels with Turning Region and Angled Ribs (I) - Cross Rib Arrangements -

각도요철 및 곡관부를 가진 회전덕트 내 압력강하 분포 (I) - 엇갈린 요철 배열 -

  • 김경민 (연세대학교 대학원 기계공학부) ;
  • 박석환 (연세대학교 대학원 기계공학부) ;
  • 이동현 (연세대학교 대학원 기계공학부) ;
  • 조형희 (연세대학교 기계공학부)
  • Published : 2006.09.01

Abstract

The present study investigates the pressure drop characteristics in rotating two-pass ducts. The duct has an aspect ratio (W/H) of 0.5 and a hydraulic diameter $(D_h)$ of 26.67mm. Rib turbulators are attached crossly in the four different arrangements on the leading and trailing surfaces of the test ducts. The ribs have a rectangular cross section of $2mm(e){\times}3mm(w)$ and an attack angle of $70^{\circ}C$. The pitch-to-rib height ratio (pie) is 7.5, and the rib height-to-hydraulic diameter ratio $(e/D_h)$ is 0.075. The results show that the highest pressure drop among each region appears in the turning region for the stationary case, but appears in the upstream region of the second pass for the rotating case. Effects of cross rib arrangements are almost the same in the first pass for the stationary and rotating cases. In the second pass, however, heat transfer and pressure drop are high for the cases with cross NN or PP type ribs in the stationary ducts. In the rotating ducts, they are high for the cases with cross NP or PP type ribs.

Keywords

References

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