Entropy generation effects with thermal radiation on MHD Casson fluid flow in porous micro-annulus

Abstract

The study of entropy generation analysis on natural convection non-Newtonian (Casson) fluid flow between two concentric cylinders/tubes is evaluated in this article. The influence of the external magnetic field normal to the flow direction with thermal radiation is analyzed on the porous surface of cylinders under the condition of Casson velocity slip and thermal jumps. The non-dimensional momentum equation of Casson fluid (CF) is solved analytically by using a modified Bessel equation containing rational number order of first and second kinds, and the energy equation is solved by using the Cauchy-Euler equation. This analysis aims to find out the loss of energy of CF flow within two cylinders and present the combinations of some parameters through which it can be minimized. Volume flow rate, entropy heat generation and irreversibility parameter are evaluated through different parameters such as the Casson parameter (CP), magnetic field parameter, Reynolds number, Brinkman number and Grashof number. Velocity is diminished for the increment of CP [Formula: see text] Volume flow rate descends with the enhancement of M and [Formula: see text] Entropy generation increased with elevation of [Formula: see text] and [Formula: see text] but reverse effects are found through higher values of [Formula: see text] Moreover, [Formula: see text] is reduced due to magnetic field and group parameter. At the end, a comparison of the velocity profile for [Formula: see text] with Abbas et al. (2019) and the volume flow rate for M with Jha et al. (2015) is established.