Irreversibility Distribution Ratio Used in Entropy Generation Equation for Convective Flows Re-visited

Abstract

The present numerical investigation describes a new consistent and accurate approach to the square cavity benchmark problems for computing entropy generation during natural or mixed convection flows. This new approach differs from the classic one in that the irreversibility distribution ratio in the dimensionless entropy generation equation is no longer arbitrarily chosen, as reported in the majority of previous research works, which is a very serious violation of the scientific rules but is precisely calculated. Indeed, the computation of the exact value of the irreversibility distribution ratio is based on two indispensable features. One concerns the thermophysical properties of the working fluid at a fixed Prandtl number or at a given reference temperature and the other concerns a reference length of the geometrical configuration considered, depending on the Rayleigh number. Comparing results indicates that the irreversibility distribution ratio, more frequently used by a significant number of researchers, is usually vastly overestimated which will involve an increase in entropy generation and, consequently, an expensive oversizing in all real processes involving flowing fluids.

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No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Saadoun Boudebous

Saadoun Boudebous obtained his diploma in hydraulics engineering in 1975 at the Polytechnic School of Algiers (ENPA). He occupied different functions in the field of hydraulics in Algerian companies, before returning to the University of Constantine in 1986. He received his diploma of Magister in 1997 and then his Ph.D. in 2002 from the University of Constantine (Algeria). He was promoted to University Professor in 2008 and has since supervised more than twenty theses of Magister and Doctoral students. His research activities include fluid mechanics, heat and mass transfer, and computational fluid mechanics.

Nawal Ferroudj

Nawal Ferroudj received her engineering degree in 2009, magister degree in 2013, and in 2023, received her Ph.D. in Chemical Engineering at the Faculty of Process Engineering of Salah Boubnider University in Constantine, Algeria. Currently, she is an assistant professor at the Higher National School of Biotechnology (ENSB) in Constantine. Her research interests include the application of numerical methods to heat and mass transfer phenomena, thermodynamics, and heat exchangers.