The Effect of Nonlinear Thermal Radiation on EMHD Casson Nanofluid over a Stretchable Riga Plate with Temperature-Dependent Viscosity and Chemical Reaction

Abstract

This study aimed to examine the flow of Electro-magnetohydrodynamic (EMHD) Casson nanofluid over a stretchable Riga plate with variable viscosity using and comparing two basic models called Reynolds’ and Vogel’s models. Brownian motion, thermophoresis, and nonlinear thermal radiation were considered. Using appropriate transformations, partial differential equations (PDEs) were converted into nonlinear ordinary differential equations (ODEs) and solved numerically using the Bvp4c method. The main goal was to visualize the effects of some parameters, such as the modified Hartmann number (0.5 ≤ E* ≤ 1.5), the Casson fluid parameter (0.3 ≤ β ≤ 1.1), the dimensionless parameter (0.5 ≤ S ≤ 1.5), the suction parameter (-0.5 ≤ fw ≤ 0.5), the Prandtl number (1 ≤ Pr ≤ 10), the radiation parameter (1 ≤ Rd ≤ 5), the space-dependent heat source (0 ≤ Q ≤ 2), the chemical reaction (0.5 ≤ γ1 ≤ 1.5), the temperature-dependent heat source (0 ≤ Q* ≤ 2), the Schmidt number (1 ≤ Sc ≤ 1.8), and the Brownian motion (0.1 ≤ Nb ≤ 0.5), on temperature and velocity profiles. The results revealed that the modified Hartmann number had a significant effect on velocity profiles, leading to the control of the flow. In addition, the increase in the radiation parameter led to an increase in the temperature.