Unsteady heat and mass transfer magnetohydrodynamic (MHD) nanofluid flow over a stretching sheet with heat source–sink using quasi-linearization technique

The current study deals with two-dimensional unsteady incompressible MHD water-based nanofluid flow over a convectively heated stretching sheet by considering Buongiorno’s model. A uniform magnetic field is applied in the direction normal to the stretching sheet. It is assumed that the lower surface of the sheet is heated by convection by a nanofluid at temperature Tf, which generates the heat transfer coefficient, hf. Uniform temperature and nanofluid volume fraction are assumed at the sheet’s surface and the flux of the nanoparticle is taken to be zero. The assumption of zero nanoparticle flux at the sheet’s surface makes the model physically more realistic. The effects of the uniform heat source–sink are included in the energy equation. With the help of similarity transformations, the partial differential equations of momentum, energy, and nanoparticle concentration are reduced to a system of nonlinear ordinary differential equations along with the transformed boundary conditions. The derived equations are solved with the help of the quasi-qinearization technique. The model is solved by considering the realistic values for the Lewis number, thermophoresis, and Brownian motion parameters. The objective of the current study is (i) to provide an efficient numerical technique for solving the boundary layer flow model and (ii) introduction of zero nanoparticle flux on the convectively heated stretching surface. The current study also focuses on the physical relevance and accurate trends of the boundary layer profiles, which are adequate in the laminar boundary layer theory. The dependence of the nanoparticle volume fraction and other pertinent parameters on the dimensionless velocity, temperature, shear stress, and heat transfer rates over the stretching surface are presented in the form of profiles.