Numerical analysis of MHD Casson nanofluid transport with Soret-Dufour cross-diffusion over a permeable stretching surface

Abstract In this study, a computational analysis is conducted to examine the steady 2-D magnetohydrodynamic (MHD) flow of Casson nanofluid (CNF) across a permeable surface influenced by the magnetic parameter, Soret and Dufour cross-diffusion and chemical reaction. Using adequate similarity transformation techniques, the resulting nonlinear boundary-value problem is solved numerically using the Keller-box method implemented in MATLAB. A comprehensive parametric study is conducted to examine how the controlling dimensionless factors impact the distributions of concentration, temperature, and momentum. The outcomes reveal that the fluid motion is suppressed with an improvement in the magnetic as well as permeability and Casson parameters, but the heat propagation increases with a rise in the Brownian motion, thermophoresis and Dufour factors. The contour of the concentration diminishes with the increase of Lewis number and the chemical reaction parameter. Results show that increasing the Casson parameter β from 1.0 to 1.5 reduces the magnitude of the wall drag by approximately 17 %, but increasing the magnetic and permeability parameters increases the wall shear stress by approximately 13 % and 27 %, respectively. Of these effects, the porous medium has the greatest influence on the drag characteristics of the flow. The numerical procedure is validated against published results, showing close agreement with the available benchmark data. The current study’s findings may assist in developing heat management systems, chemical processing equipment, and transport operations using porous media and non-Newtonian nanofluids. The linearly stretching surface is chosen for its significance in industrial processes, including polymer extrusion, wire drawing, glass production, and coating operations, where surface velocity changes linearly with the axial coordinate.