Investigation of the thermo-hydraulic behavior of the fluid flow over a square ribbed channel

Document Type : Full Lenght Research Article

Authors

School of Mechanical Engineering, University of Shahrood, Shahrood, Semnan, Iran.

Abstract

The thermo-hydraulic behavior of the air flow over a two dimensional ribbed channel was
numerically investigated in various rib-width ratio configurations (B/H=0.5-1.75) at
different Reynolds numbers, ranging from 6000 to 18000. The capability of different
turbulence models, including standard k-ε, RNG k-ε, standard k-ω, and SST k-ω, in
predicting the heat transfer rate was compared with the experimental results and it was
showed that the k-ε turbulent models best adapt with the measured data. Four main
parameters, namely, the Nusselt number, friction factor, skin friction factor, and the thermal
enhancement factor were examined through the simulations. Results indicate that an
increase in the Reynolds number caused the Nusselt number to increase and the friction
factor to drop. It was found that the thermal enhancement factor augmented by an increase
in the Reynolds number, and also, for a wider rib, i.e. at the higher the B/H ratio, a lower
thermal enhancement factor was obtained.

Keywords


[1].    J.M. Robertson, J.D. Martin and T.H. Burkhurt, Turbulent flow in rough pipes, Ind. Eng. Chem. Fundam. 7, pp. 253–265, (1963).
[2].    J. Jiménz, Turbulent flow over rough walls, Annu. Rev. Fluid Mech. 36, pp. 173–196, (2004).
[3].    R.L. Webb, Principles of enhanced heat transfer, New York: Wiley, (1994).
[4].     W.P. Jones and B.E. Launders, The Prediction of Laminarization with a Two-Equation Model of Turbulence, Int. J. Heat Mass Transfer, Vol. 15, pp. 301-314, (1972).
[5].    A.D. Gosman and A.P. Watkins, A Computer Prediction Method for Turbulent Flow and Heat Transfer in Piston/Cylinder Assemblies, Proc. of a Symposium on Turbulent Shear Flow, (1977).
[6].    B.E. Launder and D.B. Spalding, Lectures in Mathematical Models of Turbulence, Academic Press, London, (1972).
[7].    V. Yakhot and S.A. Orszag, Renormalization Group Analysis of Turbulence, I. Basic Theory,  J. Sci. Comput., Vol. 1, pp. 3-51, (1986).
[8].    W. Rodi, Turbulence Models and Their Application in Hydraulics - A State of the Art Review, IAHR, Netherlands, (1984).
[9].    DC. Wilcox, Turbulence modeling for CFD, California, USA: DCW Industries, Inc., (2000).
[10]. P. Zamankhan, Heat transfer in counterflow heat exchangers with helical turbulators, Commun Nonlinear Sci Numer Simulat, Vol. 15, pp. 2894-2907, (2010).
[11]. S. Lorenz, D. Mukomilow and W. Leiner, Distribution of the heat transfer coefficient in a channel with periodic transverse grooves, Experimental Thermal and Fluid Science, Vol. 11, pp. 234–242, (1995).
[12]. A. Chaube, P.K. Sahoo and S.C. Solanki, Analysis of heat transfer augmentation and flow characteristics due to rib roughness over absorber plate of a solar air heater, Renewable Energy, Vol. 31, pp. 317–331, (2006).
[13]. S.V. Pantankar, Numerical heat transfer and fluid flow. New York: Hemisphere, (1980).
[14]. C. Thianpong M. Pimsarn and P. Promvonge, Laminar periodic flow and heat transfer in tube with 45° angled ribs, Chiangmai University International Conference 2011, Vol. 1, No. 1 pp. 93-101, (2010).
[15]. J.C.S. Lai and C.Y. Yang, Numerical simulation of turbulence suppression: comparison of the performance of four k–e turbulence models, Int. J. Heat Fluid Flow, Vol. 18, pp. 578–584, (1997).
[16]. H. Iacovides and M. Raisee, Computation of flow and heat transfer in two-dimensional rib-roughened passages using low-Reynolds-number turbulence models, Int. J. Numer. Methods Heat Fluid Flow, Vol. 11, No. 2, pp. 138–155, (2001).
[17]. S.H. Kim and N.K. Anand, Laminar developing flow and heat transfer between a series of parallel plates with surface mounted discrete heat sources, Int. J. Heat Mass Transfer, Vol. 37, No. 15, pp. 2231–2244, (1994).
[18]. E.R. Meinders, K. Hanjalic and R. Martinuzzi, Experimental study of the local convective heat transfer from a wall mounted cube in turbulent channel flow, Trans ASME J. Heat Transfer, Vol. 121, pp. 564–573, (1991).
[19]. M. Kahrom, S.M. Javadi and P. Haghparast, Application of multi objective genetic algorithm to optimize heat transfer enhancement from a flat plate, international review of mechanical engineering, Vol. 4, No. 2, pp. 167-176, (2010).
[20]. A. Vatani, H.A. Mohammad, Turbulent nanofluid flow over periodic rib-grooved channels, Engineering Applications of Computational Fluid Mechanics, 7 (3), 369-381 (2013).