Full Length Research Paper
Abstract
Entropy generation rate in a variable viscosity liquid flowing steadily through two concentric cylindrical pipes with convective cooling at the pipe surface, are studied using the second law analysis. The outer system is assumed to exchange heat with the ambient following Newton’s cooling law, and the fluid viscosity model varies as an inverse linear function of temperature. The resulting equations and the boundary conditions are solved using the fourth Order Runge-Kutta scheme and an efficient shooting technique. Numerical expressions for fluid velocity and temperature are derived and utilised to obtain expressions for volumetric entropy generation numbers, irreversibility distribution ratio and the Bejan number in the flow field.
Key words: Pipe flow, variable viscosity, entropy generation, convective cooling, irreversibility analysis.
Copyright © 2025 Author(s) retain the copyright of this article.
This article is published under the terms of the Creative Commons Attribution License 4.0