Convective Heat Transfer Enhancement in an Enclosure with Fin Utilizing Nano Fluids

Authors: S. H. Anilkumar, Ghulam Jilani

Abstract:

The objective of the present work is to conduct investigations leading to a more complete explanation of single phase natural convective heat transfer in an enclosure with fin utilizing nano fluids. The nano fluid used, which is composed of Aluminum oxide nano particles in suspension of Ethylene glycol, is provided at various volume fractions. The study is carried out numerically for a range of Rayleigh numbers, fin heights and aspect ratio. The flow and temperature distributions are taken to be two-dimensional. Regions with the same velocity and temperature distributions are identified as symmetry of sections. One half of such a rectangular region is chosen as the computational domain taking into account the symmetry about the fin. Transport equations are modeled by a stream functionvorticity formulation and are solved numerically by finite-difference schemes. Comparisons with previously published works on the basis of special cases are done. Results are presented in the form of streamline, vector and isotherm plots as well as the variation of local Nusselt number along the fin under different conditions.

Keywords: Fin height, Nano fluid, natural convection, Rayleigh number.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1072122

References:

[1] Acharya,S., Goldstein,R,J., 1985, "Natural convection in an externally heated vertical or inclined square box containing internal energy sources", J. Heat Transfer, 107, pp.855-866.
[2] Acharya,S., Jetli,R., 1990, "Heat transfer due to buoyancy in a partially divided square box," Int. J. Heat Mass Transfer, 33 (5), pp.931-942.
[3] Scozia,R., Frederick,R,L., 1991, "Natural convection in slender cavities with multiple fins attached on an active wall", Numer. Heat Transfer A, 20, pp.127-158.
[4] Facas,G,N.,1993, "Natural convection in a cavity with fins attached to both vertical walls", J. Thermophys. Heat Transfer, 7 (4), pp.555-560.
[5] Lakhal,E,K., Hasnaoui,M., Bilgen,E., Vasseur,P.,1997, "Natural convection in inclined rectangular enclosures with perfectly conducting fins attached on the heated wall", Heat Mass Transfer, 32 (5), pp.365- 373.
[6] Keblinski, P., Phillpot,S,R., Choi,S,U,S., Eastman,J,A., 2002, "Mechanisms of heat flow in suspensions of nano-sized particles (nano fluids)", Int. J. Heat Mass Transfer, 45, pp.855-863.
[7] Shi,X., Khodadadi,J,M., 2003, "Laminar natural convection heat transfer in a differentially heated square cavity due to a thin fin on the hot wall", ASME J. Heat Transfer, 125, pp. 624-634.
[8] Khanafer,K., Vafai,K and Lightstone,M., 2003, "Buoyancy-driven heat transfer enhancement in a two-dimensional enclosure utilizing nanofluids," Int. J. Heat Mass Transfer, 46, pp.3639-3653.
[9] Brinkman H.C, 1952, "The viscosity of concentrated suspensions and solutions", J. Chem. Phys., 20, pp.571-581.
[10] Suhas V Patankar., 1980, Numerical heat transfer and fluid flow, Hemisphere Publishing Corp, New York,
[11] de Vahl Davis,G., 1983, "Natural convection of air in a square cavity: a bench mark numerical solution", Int. J. Numer. Meth. Fluids, 3, pp.249-264.
[12] Robert W Hornbeck.,1973, Numerical marching techniques for fluid flows with heat transfer, NASA, SP-297, Washington DC.
[13] Barakos,G., Mitsoulis,E., 1994, "Natural convection flow in a square cavity revisited: laminar and turbulent models with wall functions," Int. J. Numer. Meth. Fluids., 18, pp.695-719.