Numerical Investigation of Heat Transfer Enhancement with Ag-GO Water and Kerosene Oil Based Micropolar Nanofluid over a Solid Sphere

In this paper, the micro-rotation and micro-inertia characteristics of nanofluids under mixed convection boundary layer flow on a solid sphere subject to a constant surface heat flux boundary condition are considered numerically. Two types of nanoparticles namely graphene and silver suspended in two different types of fluids such as water and kerosene oil. The governing boundary layer equations and the boundary conditions are transformed into nonlinear partial differential equations system and solved numerically, via an implicit finite difference scheme namely Keller box method. The effects on the local wall temperature, the local skin friction coefficient, temperature, velocity and angular velocity are debated for several values of the parameters, namely the nanoparticle volume fraction, the micro-rotation parameter and the mixed convection parameter, by regarding the thermo-physical properties for the nanoparticles and base fluids. Furthermore, numerical results for the local heat transfer and the local skin friction coefficient are obtained, it is found that Ag/GO water has higher in local wall temperature compared with Ag/GO kerosene oil. The accuracy of the results of the local wall temperature and the local skin friction with the published results on Newtonian literature are obtained good agreement.