An Unsteady Nanofluid Flow Past Parallel Porous Plates: A Numerical Study

Abstract

This study investigates an unsteady, two dimensional, incompressible viscous boundary layer flow of an electrically conducting nanofluid past parallel plates. The plates are permeable to allow both suction and injection to take place. It is assumed that viscosity, thermal conductivity and mass diffusivity of the nanofluid vary with temperature. The novelty of this study is in the consideration of the combined effects of chemical reaction, permeability, externally applied magnetic field and momentum diffusivity on the flow varibles. The magnetic field force is significant because it provides information about the boundary layer characteristics. The highly nonlinear partial differential equations are solved numrically using the newly developed bivariate spectral quasilinearization method (BSQLM) along with varying thermal and concentration boundary conditions. The BSQLM method is an innovative technique that is more reliable and robust as it demands for fewer grid points and has a global approach of solving PDEs. An analysis and comparison of results with existing literature is reported. Excellent agreement is found between our results and those previously published. Among the findings, we show, inter alia, a significant increase in the profiles for fluid velocity, temperature and concentration with an increase in the chemical reaction, applied magnetic field, and thermal radiation. The BSQLM converges fast and is computationally efficient when applied to boundary layer problems that are defined on a large computational domain. A numerical study on nanofluid flow between parallel porous plate is carried out and here are key findings: