MHD natural convection flow of Casson fluid in an annular microchannel containing porous medium with heat generation/absorption

B.J Gireesha,S Sindhu

doi:10.1515/nleng-2020-0010

Abstract

AbstractThis study has been conducted to focus on natural convection flow of Casson fluid through an annular microchannel formed by two cylinders in the presence of magnetic field. The process of heat generation/absorption is taken into consideration. Combined effects of various parameters such as porous medium, velocity slip and temperature jump are considered. Solution of the present mathematical model is obtained numerically using fourth-fifth order Runge-Kutta-Fehlberg method. The flow velocity, thermal field, skin friction and Nusselt number are scrutinized with respect to the involved parameters of interest such as fluid wall interaction parameter, rarefaction parameter, Casson parameter and Darcy number with the aid of graphs. It is established that higher values of Casson parameter increases the skin friction coefficient. Further it is obtained that rate of heat transfer diminishes as fluid wall interaction parameter increases.

Highlights

Increase in trend towards micro scale system leads to analyze the uid ow through micro passage such as micro heat exchangers, micro nozzles and microchannel etc
This study has been conducted to focus on natural convection ow of Casson uid through an annular microchannel formed by two cylinders in the presence of magnetic eld
The ow velocity, thermal eld, skin friction and Nusselt number are scrutinized with respect to the involved parameters of interest such as uid wall interaction parameter, rarefaction parameter, Casson parameter and Darcy number with the aid of graphs

Summary

Introduction

Increase in trend towards micro scale system leads to analyze the uid ow through micro passage such as micro heat exchangers, micro nozzles and microchannel etc. Soret induced natural convection ow in an annular channel has been studied by Jha et al [20] They deliberated the heat and mass transfer analysis through channel. MHD ow of Carreau uid over a stretching sheet in the presence of homogeneous and heterogeneous reaction was investigated by Hayat et al [26] They concluded that thermal boundary layer enhances for increasing values of Biot number. Ree-Eyring uid over a parallel plate has been studied by Ramesh and Eytoo [27] considering heat transfer and slip boundary conditions They analysed the e ect of porous medium and Ree-Eyring uid parameter. Natural convection ow of an incompressible Casson uid in a vertical annular microchannel formed by two concentric cylinders with porous medium is considered. K w is Darcy number, Pr ν α is Prandtl number, Kn λ w is Knudsen number, ln βt βv is uid wall interaction parameter and β is Casson parameter

Solution procedure

Conclusions