DOI QR코드

DOI QR Code

Numerical Analysis of Thermal and Flow affected by the variation of rib interval and Pressure drop Characteristics

리브 간격 변화에 따른 열.유동 수치해석 및 압력 저하 특성

  • 정한식 (경상대학교 에너지기계공학과.해양산업연구소) ;
  • 이경환 (경상대학교 대학원 정밀기계공학과) ;
  • 신용한 (경상대학교 대학원 정밀기계공학과) ;
  • 최순호 ((주)에프티이) ;
  • 정효민 (경상대학교 에너지기계공학과.해양산업연구소)
  • Received : 2011.05.16
  • Accepted : 2011.07.21
  • Published : 2011.07.31

Abstract

The flow characteristics and heat transfer augment on the periodically arranged semi-circular ribs in a rectangular channel for turbulent flow has been investigated numerically. The aspect ratio of the rectangular channel was AR=5, the rib height to hydraulic diameter ratio were 0.07 and rib height to channel height ratio was set as e/H=0.117 for various PR(rib pitch-to-rib height rate) between 8~14, respectively. The SST k-${\omega}$ turbulence model and v2-f turbulence model were used to find out the heat transfer and the flow characteristics of near the wall which are suited to obtain realistic phenomena. The numerical analysis results show turbulent flow characteristics, heat transfer enhancement and friction factor as observed experimentally. The results predict that turbulent kinetic energy(k) is closely relative to the diffusion of recirculation flow. and v2-f turbulence model simulation results have a good agreement with experimental values.

본 연구에서는 사각채널내에 주유속 방향에 가로지르게 배치된 반원 리브의 난류 유동에 대한 유동 특성과 열전달 증대에 관해 수치해석적으로 살펴보았다. 사각채널의 종횡비는 5이고, 수력직경 대비 리브 높이비는 0.07, 사각채널 높이 대비 리브 높이비는 0.117로서 리브 높이 대비 리브 피치비가 8~14인 리브를 주기적으로 배열하여 연구를 수행하였다. 난류 모델의 선정은 실제 현상과 근접한 벽 근처 유동 특성과 열전달을 위해 SST k-${\omega}$ 난류 모델과 v2-f 난류 모델을 이용하였다. 수치해석의 결과는 실험에 의 해 관찰된 난류 유동 특성, 열전달 및 마찰계수의 결과를 잘 예측함을 보여준다. 본 결과에서 난류 운동 에너지가 재순환류 영역의 확산과 밀접한 관련이 있음을 알 수 있고 v2-f 난류 모델이 SST k-${\omega}$ 난류 모델에 비해 실험결과를 더 잘 예측하였다.

Keywords

References

  1. Liou, T. M., Hwang, J. J. and Chen, S. H.,"Simulation and measurement of enhanced turbulent heat transfer in a channel with periodic ribs on one principal wall," Int. J. Heat Mass Transfer, vol. 36, pp. 507-517,1993. https://doi.org/10.1016/0017-9310(93)80025-P
  2. Hwang J. J., "Heat transfer-friction characteristic comparison in rectangular ducts with slit and solid ribs mounted on the wall,"ASME J. Heat Transfer, vol. 120, pp.709-716, 1998. https://doi.org/10.1115/1.2824340
  3. Rau, G., Cakan, M., Moeller. D. and Arts. T.,"The effect of performance of a straight cooling channel," ASME J. Turbomachinery,vol. 120, pp. 368-375, 1998. https://doi.org/10.1115/1.2841415
  4. Yoon, J. Y., Chun, J. M., Kang. S. K. and Byun. S. J., "Evaluation of two-equation turbulence models with surface roughness effect", Trans. KSME(B), vol. 27, no. 12, pp. 1681-1690, 2003. https://doi.org/10.3795/KSME-B.2003.27.12.1681
  5. Thianpong. C., Chompookham. T., Skullong. S. and Promvonge. P., "Thermal characterization of turbulent flow in a channel with isosceles triangular ribs", International Communications in HEAT and Mass Transfer, vol. 36, pp.712-717, 2009. https://doi.org/10.1016/j.icheatmasstransfer.2009.03.027
  6. Incropera. F. and P.D. Dewitt, "Introduction to heat transfer", 3rd edition John Wiley & Sons Inc, 1996.
  7. Myong, H. K., "Numerical simulation on turbulent shear flows over surface-mounted obstacles," Trans. KSME(B), vol. 20, no. 8,pp. 2593-2600, 1996.
  8. Ooi, A., Iaccarino, G., Durbin. P. A. and Behnia. M., "Reynolds averaged simulation of flow and heat transfer in ribbed ducts," Int. J. Heat and Fluid Flow, vol. 23, pp. 750-757,2002. https://doi.org/10.1016/S0142-727X(02)00188-1
  9. Oh, S. K., Ahn, S. H. and Lee. D. H., "Effects of the wire-screen rib on heat transfer and friction factors," Journal of the Korean Society of Marine Engineering, vol. 35, no. 2, pp. 196-203, 2011 https://doi.org/10.5916/jkosme.2011.35.2.196
  10. Wilcox, D. C.,"Turbulent modeling for CFD," DCW Inc,1993.
  11. Menter, F. R., "Zonal two-equation k - ω turbulence model for aerodynamic flow," AIAA Paper, pp. 1993-2906, 1993.
  12. Durbin, P. A., "A reynolds stress model for near-wall turbulence", J. Fluid Mech., pp. 456-498. 1993. https://doi.org/10.1017/S0022112093001259