Analysis of a Reactive MHD Third Grade Fluid in a Cylindrical Pipe with Radially Applied Magnetic Field, Reynold’s Variable Viscosity and Joule Heating

Abstract

This study presents an analysis of a chemically reactive magnetohydrodynamic (MHD) third-grade fluid flowing through a cylindrical pipe. The combined effects of a radially applied magnetic field, variable viscosity, and Joule heating are examined to provide valuable insights into the fluid’s behaviour, with important implications for optimising industrial processes and enhancing the performance of systems that utilise MHD fluids. The coupled governing equations are formulated, and the Reynolds viscosity model is adopted and approximated using Taylor series expansion. The resulting non-linear dimensionless equations are solved numerically using the Galerkin weighted residual method. A parametric study of the relevant physical parameters is presented graphically and discussed. The results indicate that the velocity profile exhibits an inverse relationship with the magnetic parameter, while the Bejan number increases with increasing magnetic parameter and decreases with increasing Hall parameter.

Keywords: Magnetohydrodynamics, variable viscosity, Joule heating, Bejan number

Citation: Akinremi. B.V. (2026). Analysis of a Reactive MHD Third Grade Fluid in a Cylindrical Pipe with Radially Applied Magnetic Field, Reynold’s Variable Viscosity and Joule Heating. Journal of Education, Science and Technology 2026, (1) 1.111-123.

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