Entropy generation in laminar natural convection from a constant temperature vertical plate in an infinite fluid

Abstract In the work presented here, the entropy generation due to heat transfer and fluid flow has been carried out for laminar natural convection from a constant temperature vertical plate in an infinite fluid. Fluid flow and heat transfer characteristics on a constant temperature vertical plate are some of the fundamental problems in engineering. The problem is discussed by considering the entropy generation profiles and the heat transfer irreversibility characteristics. An analytical expression, in terms of entropy generation number (NG) and Bejan number (Be) are derived in dimensionless form using velocity and temperature profiles. In addition, temperature profiles, entropy generation profiles and flow profiles characteristics, and relations between them are figured out. Obviously the maximum temperature line along the vertical plate corresponds to the maximum entropy generation line. The mechanism responsible for that is the enhancement in heat transfer rates and fluid friction in this region. Also, another important issue noticed during the analysis is the wall itself which emerges as a source of irreversibility or powerful entropy generator.

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