A new theoretical tri-hybrid nanofluid model for enhancing the heat transfer is presented in this article. This model explains the method to obtain a better heat conductor than the hybrid nanofluid. The tri-hybrid nanofluid is formed by suspending three types of nanoparticles with different physical and chemical bonds into a base fluid. In this study, the nanoparticles TiO2, Al2O3 and SiO2 are suspended into water thus forming the combination TiO2-SiO2-Al2O3-H2O. This combination helps in decomposing harmful substances, environmental purification and other appliances that requires cooling. The properties of tri-hybrid nanofluid such as Density, Viscosity, Thermal Conductivity, Electrical Conductivity and Specific Heat capacitance are defined mathematically in this article. The system of equations that governs the flow and temperature of the fluid are converted to ordinary differential equations and are solved using RKF-45 method. The results are discussed through graphs and it is observed that the tri-hybrid nanofluid has a better thermal conductivity than the hybrid nanofluid.

The main emphasis of the present study is to discuss the effect of chemical reaction on flow, heat, and mass transfer of Williamson nanofluid over a stretching sheet. The flow is considered under the influence of nonlinear thermal radiation. To obtain the numerical results, the governing equations have been reduced to a set of nonlinear ordinary differential equations using appropriate similarity transformations. An efficient Runge-Kutta-Felhberg 45 order method along with a shooting technique is used to get the required solutions. The accuracy of the method used is verified with the existing results, and they are found to be in good agreement. Obtained numerical solutions are presented in the form of graphs and tables for a various range of slip boundary condition and for different values of flow pertinent parameters, such as permeability parameter, radiation parameter, Lewis number, Heat capacities ratio, diffusivity ratio, Schmidt number, chemical reaction parameter, volumetric volume expansion...