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http://dx.doi.org/10.3795/KSME-B.2012.36.9.923

Effects of Prandtl Numbers on Heat Transfer of Backward-Facing Step Laminar Flow with a Pulsating Inlet  

Kim, Won-Hyun (School of Mechanical Engineering, Kyungpook Nat'l Univ.)
Park, Tae-Seon (School of Mechanical Engineering, Kyungpook Nat'l Univ.)
Publication Information
Transactions of the Korean Society of Mechanical Engineers B / v.36, no.9, 2012 , pp. 923-930 More about this Journal
Abstract
The wall heat transfer of backward-facing step laminar flows with different Prandtl numbers and a pulsating inlet is investigated by unsteady simulations. The inlet is perturbed by the variation of frequency and amplitude. Temperature-dependent transport properties are adopted. Various characteristics of the wall heat transfer are explained by the variation of the thermal boundary layer. For Pr < 1, the wall heat transfer of temperature-dependent properties is decreased compared to that of constant properties, whereas it increases for Pr < 1. In addition, the wall heat transfer increases depending on the pulsating amplitude. However, the results of frequency variation for St < 0.2 show that the heat transfer is strongly enhanced at a specific frequency. In particular, the increase in the wall heat transfer is strongly related to the root mean square of the fluctuations of the reattachment length.
Keywords
Reattachment Length; Thermal Boundary Layer Thickness; Inlet Pulsation; Nusselt Number; Prandtl Number;
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1 Park, H. M., Jeon, W. P., Choi H. C. and Yoo, J. Y., 2007, "Mixing Enhancement Behind a Backward-Facing Step Using Tabs," Physics of Fluids, Vol 19, No 10, pp. 105103-105103-12.   DOI   ScienceOn
2 Rhee, G. H. and Sung, H. J., 2000, "Numerical Prediction of Locally Forced Turbulent Separated and Reattaching Flow," Fluid Dynamics Research, Vol 26, No 6, pp. 421-436.   DOI   ScienceOn
3 Valencia, A. and Hinojosa, L., 1997, "Numerical Solutions of Pulsating Flow and Heat Transfer Characteristics in a Channel with a Backward- Facing Step," Heat and Mass Transfer, Vol 32, No 3, pp. 143-148.   DOI
4 Khanafer, K., Azmi, B. A., Shammari, A. A. and Pop, I., 2008, "Mixed Convection Analysis of Laminar Pulsating Flow and Heat Transfer over a Backward Facing Step," International Journal of Heat and Mass Transfer, Vol 51, No 25-26, pp. 5785-5793.   DOI   ScienceOn
5 Velazquez, A., Arias, J. R. and Mendez, B., 2008, "Laminar Heat Transfer Enhancement Downstream of a Backward Facing Step by Using a Pulsating Flow," International Journal of Heat and Mass Transfer, Vol 51, No 7-8, pp. 2075-2089.   DOI   ScienceOn
6 Yu, J. C., Li, Z. X. and Zhao, T. S., 2004 "An Analytical Study of Pulsating Laminar Heat Convection in a Circular Tube with Constant Heat Flux," International Journal of Heat and Mass Transfer, Vol 47, No 24, pp. 5297-5301.   DOI   ScienceOn
7 Hemida, H. N., Sabry, M. N., Abdel-Rahim, A. and Mansour, H., 2002, "Theoretical Analysis of Heat Transfer in Laminar Pulsating Flow," International Journal of Heat and Mass Transfer, Vol 45, No 8, pp. 1767-1780.   DOI   ScienceOn
8 Park, T. S., 2006, "Effects of Time-Integration Method in a Large-Eddy Simulation Using the PISO Algorithm: Part I-Flow Field," Numerical Heat Transfer Part A, Vol 50, No 3, pp. 229-245.   DOI   ScienceOn
9 Chen, X. B., Yu, P., Winoto, S. H. and Low, H. T., 2008, "Forced Convection Over a Backward- Facing Step with a Porous Floor Segment," Numerical Heat Transfer Part A, Vol 53, No 11, pp. 1211-1230.   DOI   ScienceOn
10 Inaoka, K., Nakamura, K. and Senda, M., 2004, "Heat Transfer Control of a Backward-Facing Step Flow in a Duct by Means of Miniature Electromagnetic Actuators," International Journal of Heat and Fluid Flow, Vol 25, No 5, pp. 711-720.   DOI   ScienceOn
11 Armaly, B. F., Durst, F., Pereira, J. C. F. and Schonung, B., 1983, "Experimental and Theoretical Investigation of Backward-Facing Step Flow," Journal of Fluid Mechanics, Vol 127, pp. 473-496.   DOI   ScienceOn
12 Issa, R. I., 1985, "Solution of the Implicitly Discretised Fluid Flow Equations by Operator- Splitting," Journal of Computational Physics, Vol 62, No 1, pp. 40-65.
13 Zografos, A. I., Martin, W. A. and Sunderland, J. E., 1987, "Equations of Properties as a Function of Temperature for Seven Fluids," Computer Methods in Applied Mechanics and Engineering, Vol 61, No 2, pp. 177-187.   DOI   ScienceOn
14 Khan, M. H., 2004, "Modeling, Simulation and Optimization of Ground Source Heat Pump Systems," Ph. D. Dissertation, Oklahoma State University.
15 Sparrow, E. M., Kang, S. S. and Chuck, W., 1987, "Relation Between the Points of Flow Reattachment and Maximum Heat Transfer for Regions of Flow Separation," International Journal of Heat and Mass Transfer, Vol 30, No 7, pp. 1237-1246.   DOI   ScienceOn