Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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Detailed Measurement of Heat/Mass Transfer in a Rotating Two-Pass Duct (I) - Effects of Rib Tubulators -

이차 냉각 유로를 가진 회전덕트에서 열/물질전달 특성 (I) - 요철 설치에 따른 영향 -

  • 김경민 (연세대학교 대학원 기계공학과) ;
  • 김상인 (연세대학교 대학원 기계공학과) ;
  • 김윤영 (연세대학교 대학원 기계공학과) ;
  • 이동호 (연세대학교 대학원 기계공학과) ;
  • 조형희 (연세대학교 기계공학과)
  • Published : 2004.08.01
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Abstract

The heat/mass transfer characteristics in a rotating two-pass duct with and without rib turbulators are investigated in the present study. The square duct has a hydraulic diameter ($D_h$) of 26.7 mm, and $1.5\;mm{\times}1.5\;mm$ square $90^{\circ}$-rib turbulators are attached on the leading and trailing walls. The pitch-to-rib height ratio (p/e) is 10. The Reynolds number based on the hydraulic diameter is kept constant at 10,000 to exclude the Reynolds effect, and the rotation number is varied from 0.0 to 0.20. In the smooth duct, the curvature of the $180^{\circ}$-turn produces Dean vortices that enhance heat/mass transfer in the post-turn region. When rib turbulators are installed, heat/mass transfer is augmented 2.5 times higher than that of the smooth duct since the main flow is turbulated by reattaching and separating in the vicinity of the duct surfaces. The duct rotation results in heat/mass transfer discrepancy so that Sherwood number ratios are higher on the trailing surface in the first-pass and on the leading surface in the second-pass. In the turning region, Dean vortices shown in the stationary case transform into one large asymmetric vortex cell, and subsequent heat/mass transfer characteristics also change. As the rotation number increases, the heat/mass transfer discrepancy enlarges.

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References

  1. Liou, T. M., Chen, C. C. and Chen, M. Y., 2001. 'TLCT and LDV Measurements of Heat Transfer and Fluid Flow in a Rotating Sharp Turning Duct,' Int. J. Heat and Mass Transfer, Vol. 44, pp. 1777-1787 https://doi.org/10.1016/S0017-9310(00)00221-0
  2. Han, J. C., Chandra, P. R. and Lau, S. C., 1988, 'Local Heat/Mass Transfer Distributions Around Sharp 180 Deg Turns in Two-Pass Smooth and Rib-Roughened Channels,' Journal of Heat Transfer, Vol. 110, pp. 91-98 https://doi.org/10.1115/1.3250478
  3. Parsons, J. A., Han, J. C. and Zhang, Y. M., 1994, 'Wall Heating Effect on Local Heat Transfer in a Rotating Two-Pass Square Channel with $90^{\circ}Rib$ Turbulators,' Int. J. Heat Mass Transfer, Vol. 37, pp. 1411-420 https://doi.org/10.1016/0017-9310(94)90187-2
  4. Al-Qahtani, M., Jang, Y. J., Chen, H. C. and Han, J. C., 2002, 'Flow and Heat Transfer in Rotating Two-Pass Rectangular Channels (AR=2) by Reynolds Stress Turbulence Model,' Int. J. Heat Mass Transfer, Vol. 45, pp. 1823-1838 https://doi.org/10.1016/S0017-9310(01)00292-7
  5. Mochizuki, S., Murata, A., Shibata, R. and Yang, W. J., 1999, 'Detailed Measurement of Local Heat Transfer Coefficients in Turbulent Flow Through Smooth and Rib-Roughened Serpentine Passages with a $180^{\circ}$ Sharp Bend,' Int. J. Heat and Mass Transfer, Vol. 42, pp. 1925-1934 https://doi.org/10.1016/S0017-9310(98)00308-1
  6. Iacovides, H., Jackson, D. C., Kelemenis, G., Launder, B. E. and Yuan, Y. M., 1999, 'Experiments on Local Heat Transfer in a Rotating Square-Ended U-bend,' Int. J. Heat and Fluid Flow, Vol. 20, pp. 302-310 https://doi.org/10.1016/S0142-727X(99)00019-3
  7. Iacovides, H., Jackson, D. C., Kelemenis, G., Launder, B. E. and Yuan, Y. M., 2001, 'Flow and Heat Transfer in a Rotating U-bend with $45^{\circ}Ribs$,' Int. J. Heat and Fluid Flow, Vol. 22, pp. 308-314 https://doi.org/10.1016/S0142-727X(01)00093-5
  8. Won, J. H., Lee, S. Y. and Cho, H. H., 2001, 'Heat/Mass Transfer Characteristics in a Rotating Duct with $180^{\circ}$ Turn,' Transactions of the KSME(B), Vol. 25, No. 3, pp. 405-413
  9. Lee, S. Y., Won J. H., Choi, C. and Cho, H. H., 2000, 'Heat/Mass Transfer in Rotating Cooling Passage of Turbine Blade,' Proceedings of Energy and Power Division 2000 Fall Annual Meeting, pp. 46-54
  10. Cho, H. H., Lee, S. Y. and Rhee, D. H., 2001, 'Heat Transfer Characteristics in a Two-Pass Rotating Rectangular Duct with $70^{\circ}Attack$ Angle Ribs,' International Conference on Energy Conversion and Application (ICECA 2001), pp. 605-610
  11. Cho, H. H., Kim, Y. Y., Kim, K. M. and Rhee, D. H., 2003, 'Effects of Rib Arrangements and Rotating Speed on Heat Transfer in a Two-Pass Duct,' ASME Paper No. GT-2003-38609
  12. Goldstein, R. J. and Cho, H. H. 1995, 'A Review of Mass Transfer Measurements Using Naphthalene Sublimation,' Experimental Thermal and Fluid Science, Vol. 10, pp. 416-434 https://doi.org/10.1016/0894-1777(94)00071-F
  13. Kline, S. J. and McClintock, F. A., 1953, 'Describing Uncertainty in Single-Sample Experiments,' Mechanical Engineering, Vol. 75, pp. 3-8
  14. McAdams, W. H., 1942, 'Heat Transmission, 2nd Edition,' McGraw-Hill, New York
  15. Chandra, P. R. and Han, J. C., 1989, 'Pressure Drop and Mass Transfer in Two-Pass Ribbed Channels,' J. Thermophysics, Vol. 3, No. 3, pp. 315-320 https://doi.org/10.2514/3.28787