Abstract
The inherent irreversibility and thermal stability in a gravity-driven temperature-dependent variable viscosity thin liquid film along an inclined heated plate with convective cooling is investigated. In this study, both the isothermal and isoflux heating of the plate are considered. The free surface of the liquid film is assumed to exchange heat with the surroundings following Newton’s cooling law and the fluid viscosity model varies as an inverse linear function of the temperature. Analytical solutions are constructed for the governing boundaryvalue problem, and important properties of velocity and temperature fields such as thermal stability criterion are obtained. Expressions for volumetric entropy generation numbers, irreversibility distribution ratio, and the Bejan number in the flow field are also obtained and discussed quantitatively.
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This paper was recommended for publication in revised form by Associate Editor Tong Seop Kim
Oluwole Daniel Makinde is currently Senior Professor and Chair of Postgraduate Studies in the Faculty of Engineering Cape-Peninsula University of Technology (CPUT) in South Africa. Prior to joining CPUT, he was a Professor and Head of Applied Mathematics Department for many years at University of Limpopo, South Africa. He received his B.Sc. (Hons) First Class and M.Sc. from Obafemi Awolowo University, Ile-Ife, Nigeria and PhD at University Bristol, England all in Computational and Applied Mathematics. Professor Makinde has taught supervised graduate students and served as an external examiner at many universities within and outside Africa. He has co-authored two applied mathematics textbooks, two Open University monographs on Particle Mechanics and Incompressible Flow Theory and published numerous research articles in several reputable international journals. He is presently the Secretary General of African Mathematical Union. Professor Makinde received Best Senior Research Scientists Award at University of Limpopo African Mathematician Medal for Excellence in Applied Mathematics and many other awards and grants.
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Makinde, O.D. Thermodynamic second law analysis for a gravity-driven variable viscosity liquid film along an inclined heated plate with convective cooling. J Mech Sci Technol 24, 899–908 (2010). https://doi.org/10.1007/s12206-010-0215-9
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DOI: https://doi.org/10.1007/s12206-010-0215-9