Ternary cobalt ferrite (CoFeO4)-silver (Ag)-titanium dioxide (TiO2) hybrid nanofluid hydromagnetic nonlinear radiative-convective flow from a rotating disk with viscous dissipation, non-Darcy and non-Fourier effects: Swirl coating simulation

Abstract

Magnetic nanoparticles are increasingly being deployed in smart coating systems due to their exceptional functionalities and abilities to be tuned for specific environmental conditions. Inspired by the emergence of tri-hybrid magnetic nanofluids which utilize three distinct nanoparticles in a single base fluid coating, the present article examines analytically and computationally the swirl coating of magnetic ternary hybrid nanofluid from a rotating disk, as a simulation of spin coating deposition processes in materials manufacturing. Owing to high temperature fabrication conditions, thermal radiative heat transfer is also considered and a Rossleand flux model deployed. -- hybrid nanoparticles are considered with Ethylene Glycol-Water () base fluid. A filtration medium is also featured (porous medium) adjacent to the disk and the Darcy-Forchheimer model is deployed to simulate both bulk matrix porous drag encountered at lower Reynolds numbers and inertial quadratic drag generated at higher Reynolds numbers. Thermal relaxation of the coating nanofluid is additionally addressed and a non-Fourier Cattaneo-Christov model is therefore implemented in the heat conservation equation. Viscous dissipation is also included in the model. The governing conservation equations for mass, momenta (radial, tangential and axial) and energy with prescribed boundary conditions are rendered into coupled nonlinear ordinary differential boundary layer equations via suitable scaling variables and the Von Karman transformations. The derived reduced boundary value problem is then solved with a Runge-Kutta numerical scheme and shooting scheme in MATLAB. Validation of solutions is included with previous studies. Radial and azimuthal velocities, temperature, radial skin-friction, azimuthal skin friction and local Nusselt number are computed for a range of selected parameters. A comparative assessment of mono nanofluid Hybrid - nanofluid and tri-Hybrid -- nanofluid is conducted. This combination of hybrid nanoparticles has never been examined previously in the literature and constitutes the significant novelty of the present work. Both radial and tangential velocity are depleted with increasing applied magnetic field whereas temperature and thermal boundary layer thickness are increased.