Entropy generation in Rayleigh-Bénard problem for different geometrical cavities

Year 2017, Volume: 20 Issue: 4, 200 - 208, 29.11.2017

Omar Al-abbasi

https://doi.org/10.5541/eoguijt.314253

Cited By: 1

Abstract

Entropy
generation for the natural convection phenomena is studied for different
geometrical cavities that have identical boundary conditions and unit area. The
key characteristic parameter in this study was the Grashof number. The effect
of Grashof number on Nusselt number and entropy generation has been studied
using finite element method. The developed models in this study were validated
against published work in the literature and results were found to be in close
agreement. Entropy generation was found to increase with an increase in the
Grashof number and the heat transfer was the dominant factor in increasing the
entropy generation. A lower entropy generation is generally expected with an
increase in the distance between the hot and cold boundaries. It is also noted
that the rate of entropy generation decreases slowly when the flow domain is
only slightly distorted, while the rate of entropy generation increases sharply
when the flow domain changes significantly.  

Keywords

Rayleigh-Bénard, entropy generation, heat transfer

References

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