Magnetohydrodynamic micropolar nanofluid flow over a vertically elongating sheet containing gyrotactic microorganisms with temperature-dependent viscosity

Abstract

Magnetohydrodynamic bioconvective micropolar nanofluid flow with migrating microorganisms opens up an intriguing new field in materials science. The distribution of particles during processing, such as metal casting, polymer extrusion, etc., can affect material characteristics and final product quality. So, the current research examines magnetohydrodynamic micropolar nanofluid flow over a vertically extending material in the presence of swimming microorganisms. The mathematical model also considers the temperature dependence of dynamic viscosity with thermal radiation using the Rosseland approximation, Brownian diffusion, and the thermo-migration of microscopic particles. Similarity variables are used to convert the partial derivatives to ordinary derivatives. Then the Runge-Kutta-Gill method is used with the shooting technique to obtain a numerical solution to the resulting set of equations. Various tables and graphs are included to illustrate the impact of the emerging parameters on the flow fields. Results show that an increase in the material parameter improves fluid mobility but decreases the skin friction coefficient, whereas the magnetic field term exhibits the opposite behaviour due to friction induced by the Lorentz force. The analysis shows that the thermal field significantly expands as the thermo-migration of tiny particles and Brownian motion get stronger.