Water-Based Fe3O4 Ferrofluid Flow Between Two Rotating Disks with Variable Viscosity and Variable Thermal Conductivity

Abstract

The impact of variable viscosity and variable conductivity is presented on the water-based Fe3O4 nanofluid flow between two parallel stretchable rotating disks. The stretching and rotating rates of both disks play an essential role in velocity distribution and heat transfer study. The similarity transformation is utilized to customize the momentum and energy equations into nonlinear-coupled differential equations with some influential dimensionless physical parameters. The nonlinear-coupled differential equations of the transformed system are solved numerically through the finite element method using COMSOL Multiphysics. The outcomes for velocity and temperature distributions are shown in the presence of considered physical parameters in the flow. Enhancing the stretching of disks, rotation speed, and variable thermal conductivity enhances the temperature of nanofluid. Permeability parameter, ferromagnetic interaction numbers, and Reynolds numbers also have a major role in the velocity and temperature distributions. Strengthening the rotation number, ferromagnetic interaction number and Reynolds number amplifies the friction on the surface of the disk and shrinks the local heat transfer rate. The rheological behavior of ferrofluid and the role of variable thermal conductivity in the present study might be useful to select the best possible nanofluid for medical purposes.