On model for three-dimensional flow of nanofluid: An application to solar energy

Laminar three-dimensional flow of nanofluid over a bi-directional stretching sheet is investigated. Convective boundary conditions are used for the analysis of thermal boundary layer. Mathematical model containing the combined effects of Brownian motion and thermophoretic diffusion of nanoparticles is adopted. The formulated differential system is solved numerically using a shooting method with fourth-fifth-order Runge-Kutta integration technique. The solutions depend on various interesting parameters including velocity ratio parameter (λ), Brownian motion parameter (Nb), thermophoresis parameter (Nt), Prandtl number (Pr), Lewis number (Le) and the Biot number (γ). It is noticed that fields are largely influenced with the variations of these parameters. The results are compared with the existing studies for the two-dimensional flows and found in an excellent agreement. The study reveals that nanoparticles in the base fluid offer a potential in improving the convective heat transfer performance of various liquids.