Unsteady magnetohydrodynamic flow and heat transfer of nanofluid and hybrid nanofluids over a vertical cone embedded in a porous medium

Abstract

Nanotechnology has played a significant role in multi-fields of heat transfer processes and has made impressive advances in energy applications. This technology has significantly developed the science of thermal energy by improving various properties of energy transmitting fluids. This includes the development of nanofluid that can provide high heat transfer rates in a thermal energy system. Anewclass of nanofluid is known as hybrid nanofluid. Hybrid nanofluid has better chemical and mechanical strength, excellent thermal and electrical conductivity, lower cost, high heat transfer rates, and reliable physio-chemical properties. Bearing in mind such interesting features of nanofluid, the predominant idea of this thesis is to investigate heat transfer in the boundary layer flow of unsteady viscous nanofluids and hybrid nanofluid. Specifically, the water based nanofluids and hybrid nanofluid flow along a vertical cone enclosed in a porous medium is considered. The effects of external magnetic field and thermal radiation are additional features to the innovation of the constructed mathematical model. The system of nonlinear coupled equation supported by related initial and boundary conditions are solved numerically by using finite difference method. In the analysis, the impact of various physical parameters are scrutinized and the results are exhibited graphically. The physical quantities of wall shear stress and heat transfer coefficient versus governing constraints are evaluated and their results are summarized in the form of tables. The heat transfer performance of hybrid nanofluid is compared with the performance of nanofluid. The results show that the thermal performance of the system increases in the presence of magnetic field and thermal radiation. In addition, high heat transfer rates are observed when the flow is induced by varied heat flux as compared to varied wall temperature. Moreover, the viscosity is also responsible to enhance the heat transfer rates of the fluids. This research contributes to a better understanding on the effects of magnetohydrodynamic in mixed convection for radiative hybrid nanofluid flow.