Hostname: page-component-78c5997874-t5tsf Total loading time: 0 Render date: 2024-11-10T16:04:35.956Z Has data issue: false hasContentIssue false

Evaporation of Non-Newtonian Fluid in Porous Medium Under Mixed Convection

Published online by Cambridge University Press:  05 May 2011

M.-H. Shih*
Affiliation:
Department of Mechanical Engineering, Chinese Military Academy, Fengshan, Taiwan 83059, R.O.C.
W.-J. Luo*
Affiliation:
Department of Refrigeration, Air-Conditioning and Energy Engineering, National Chin-Yi University of Technology, Taichung County, Taiwan 41101, R.O.C.
K.-C. Yu*
Affiliation:
Department of Refrigeration, Air-Conditioning and Energy Engineering, National Chin-Yi University of Technology, Taichung County, Taiwan 41101, R.O.C.
*
*Assistant Professor
*Assistant Professor
**Lecturer
Get access

Abstract

This study investigates the problem of non-Newtonian liquid evaporation from an impermeable vertical plate in a porous medium under mixed convection conditions. The analysis examines the effects of non-Darcian flow phenomena on the evaporation process and investigates the heat and mass transfer characteristics under a range of flow conditions in the aiding and opposing flow types. The parameters of interest include Rak,non, Pex,non, Pr and Sc. The data required for the calculations include a fixed wall temperature of Tw = 45°C, a free flow temperature of T∞ = 20°C and an air free flow rate of u∞ = 4m/sec and the corresponding humidity of 50% flows over fixed temperature and moist wall.

The results indicate that an increasing buoyancy force enhances the mixing effect and therefore improves the rate of heat transfer, the latent heat flux is the primary mode of heat transfer in evaporation processes and the velocity gradient at the wall increases with an increasing buoyancy effect. Furthermore, the evaporation rate increases with a reducing flow index and an increasing buoyancy effect.

Type
Articles
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1.Cheng, P., “Combined Free and Forced Convection Flow about Inclined Surface in Porous Media,” Int. J. Heat Mass Transfer, 20, pp. 807814 (1977).Google Scholar
2.Bejan, A. and Poulikakos, D., “The Non-Darcy Regime for Vertical Boundary Layer Natural Convection in a Porous Medium,” Int. J. Heat Mass Transfer, 27, pp. 717722 (1984).CrossRefGoogle Scholar
3.Ranganathan, P. and Viskanta, R., “Mixed Convection Boundary-Layer Flow along a Vertical Surface in a Porous Medium,” Numerical Heat Transfer, 7, pp. 305317(1984).CrossRefGoogle Scholar
4.Hong, J. T., Tien, C. L. and Kaviany, M., “Non- Darcian Effects on Vertical-Plate Natural Convection in Porous Media with High Porosities,” Int. J. Heat Mass Transfer, 28, pp. 21492157 (1985).CrossRefGoogle Scholar
5.Chen, K. S. and Ho, J. R., “Effects of Flow Inertia on Vertical Natural Convection in Saturated Porous Media,” Int. J. Heat Mass Transfer, 29, pp. 753759 (1986).CrossRefGoogle Scholar
6.Cheng, C.-Y., “Natural Convection Heat and Mass Transfer from a Horizontal Cylinder of Elliptic Cross Section with Constant Wall Temperature and Concentration in Saturated and Concentration in Saturated Porous Media,” Journal of Mechanics, 22, pp. 257261 (2006).CrossRefGoogle Scholar
7.Lauriat, G. and Prasad, V., “Non-Darcian Effects on Natural Convection in a Vertical Porous Enclosure,” Int. J. Heat Mass Transfer, 32, pp. 21352148 (1989).CrossRefGoogle Scholar
8.Yih, K. A., “Heat Source/Sink Effect on MHD Mixed Convection on Stagnation Flow on a Vertical Permeable Plate in Porous Media,” Int. Comm. Heat Mass Transfer, 25, pp. 427442 (1998).CrossRefGoogle Scholar
9.Khaled, A. R. A. and Varfi, K., “The Role of Porous Media in Modeling the Flow and Heat Transfer in Biological Tissues,” Int. J. Heat Mass Transfer, 46, pp. 49895003 (2003).CrossRefGoogle Scholar
10.Yan, W. N., “Evaporative Cooling of Liquid Film in Turbulent Mixed Convection Channel Flows,” Int. J. Heat Mass Transfer, 41, pp. 37193729 (1998).CrossRefGoogle Scholar
11.Huang, M. J. and Lin, B. L., “Forced Convective Flow Over a Flat Plate in Non-Newtonian Power Law Fluids,” Warme und Stoffubertragung, 27, pp. 399404 (1992).CrossRefGoogle Scholar
12.Hsieh, J. C., Chen, T. S. and Armaly, B. F., “Nonsimilarity Solutions for Mixed Convection from Vertical Surface in Porous Media: Vaiable Surface Temperature or Heat Flux,” Int. J. Heat Mass Transfer, 36, pp. 14851493 (1993).CrossRefGoogle Scholar
13.Rastogi, S. K. and Poulikakos, D., “Double- Diffusion from a Vertical Surface in a Porous Region Saturated with a Non-Newtonian Fluid,” Int. J. Heat Mass Transfer, 38, pp. 935946 (1995).CrossRefGoogle Scholar
14.White, F. M., Viscous Fluid Flow, McGraw-Hill, New York (1991).Google Scholar
15.Forchheimer, P. H.durch Boden, Wasserbewegun, Zeitschrift des Vereins, Deutscher Ingenieure, 45, pp. 17821788 (1901).Google Scholar
16.Brinkman, H. C., “A Calculation of the Viscous Force Exerted by a Flowing Fluid on a Dense Swarm Particles,” Appl. Sci. Res., 1, pp. 2734 (1974).CrossRefGoogle Scholar
17.Shih, M. H. and Huang, M. J., “A study of Liquid Evaporation on Forced Convection in Porous Media with Non-Darcy Effects,” Acta Mechanica, 154, 215231 (2002).CrossRefGoogle Scholar
18.Cebeci, T., Bradshaw, P., Physical and Computational Aspects of Convective Heat Transfer, Springer, New York, p. 385 (1984).CrossRefGoogle Scholar
19.Gorla, R. S. R. and Kumari, M., “Mixed Convec-tion in Non-Newtonian Fluids along a Vertical pp. Plate in a Porous Medium,” Acta Mechanic, 118, pp. 5564 (1996).CrossRefGoogle Scholar