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Rectangular-Plate Turbulator Effects on Heat Transfer and Near-Wall Flow Characteristics in Fan Flows

Published online by Cambridge University Press:  05 May 2011

T.Y. Chen  and
Y.H. Chen
T.Y. Chen*
Affiliation:
Department of Aerospace Engineering, Tamkang University, Taipei, Taiwan25137, R.O.C
Y.H. Chen*
Affiliation:
Department of Aerospace Engineering, Tamkang University, Taipei, Taiwan25137, R.O.C
*
* Professor
** Research Assistant
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Abstract

Heat transfer and near-wall flow characteristics in an inherently swirling fan flow, containing rectangular-plate turbulators with 45° and 90° angles of attack, were experimentally investigated. The heat transfer characteristics for uniform flows with the turbulators were also investigated for comparison. Eight heated aluminum plates, installed along a bottom duct-wall, were used as the heat transfer surfaces, which allows the studies of heat transfer variations along the duct and the studies of the relations between the local fluid flows and heat transfer variations. Three-component mean and fluctuating velocities were measured using a laser Doppler velocimetry to obtain the near-wall flow parameters, including the axial mean velocity, axial vorticity and turbulent kinetic energy. The temperatures on the eight heat transfer surfaces were measured using thermocouples to obtain the Stanton number distributions. Results suggest that the rectangular-plate turbulators in fan flows may cause the increases in the near-wall flow parameters and, consequently, augment the heat transfer, especially around the flow reattachment regions. Also, the rectangular-plate turbulator effect on heat transfer augmentation in fan flows may be as attractive as that in uniform flows at the investigated X/H ranges.

Keywords

fan flowturbulatorheat transfer
Type
Articles
Information
Journal of Mechanics , Volume 20 , Issue 1 , March 2004 , pp. 33 - 41
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2004

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References

1.Eibeck, P. A. and Eaton, J. K., “Heat Transfer Effects of a Longitudinal Vortex Embedded in Turbulent Boundary Layer,” J. of Heat Transfer, 109, pp. 16–24 (1987).Google Scholar
2.Fiebig, M., Kallweit, P., Mitra, N. and Tiggelbeck, S., “Heat Transfer Enhancement and Drag by Longitudinal Vortex Generators in Channel Flow,” Experimental Thermal and Fluid Science, 4, pp. 103–114 (1991).CrossRefGoogle Scholar
3.Tiggelbeck, S., Mitra, N. and Fiebig, M, “Comparison of Wing-Type Vortex Generators for Heat Transfer Enhancement in Channel Flows,” J. of Heat Transfer, 116, pp. 880–885 (1994).Google Scholar
4.Biswas, G., Torii, K., Fujii, D. and Nishino, K., “Numerical and Experimental Determination of Flow Structure and Heat Transfer Effects of Longitudinal Vortices in a Channel Flow,” International J. of Heat and Mass Transfer, 39(16), pp. 3441–3451 (1996).CrossRefGoogle Scholar
5.Tsia, J. P. and Hwang, J. J., “Measurements of Heat Transfer and Fluid Flow in a Rectangular Duct with Alternate Attached-Detached Rib-Arrays,” International J. of Heat and Mass Transfer, 42, pp. 2071–2083 (1999).CrossRefGoogle Scholar
6.Liou, T. M. and Hwang, J. J., “Effect of Ridge Shapes on Turbulent Heat Transfer and Friction in a Rectangular Channel,” International J. of Heat and Mass Transfer, 36(4), pp. 931–940 (1993).CrossRefGoogle Scholar
7.Liou, T. M., Chen, C. C., Tzeng, Y. Y. and Tsai, T. W., “Non-Intrusive Measurements of Near-Wall Fluid Flow and Surface Heat Transfer in a Serpentine Passage,” International J. of Heat and Mass Transfer, 43, pp. 3233–3244 (2000).CrossRefGoogle Scholar
8.Ligrani, P. M., Mahmood, J. L., Harrison, C. M., Clayton, D. L. and Nelson, D. L., “Flow Structure and Local Nusselt Number Variations in a Channel with Dimples and Protrusions on Opposite Walls,” Int. J. of Heat and Mass Transfer, 44, pp. 4413–4425 (2001).CrossRefGoogle Scholar
9.Kays, W. M. and Crawford, M. E., ”Convective Heat and Mass Transfer,” 2nd ed., McGraw-Hill, New York, pp. 250–256 (1980).Google Scholar