## 2 Nanofluids: Techniques and Applications
In the paper [4], the heat and mass transfer characteristics of two water-based fractional nanofluids, containing nanoparticles of CuO and Ag, over an infinite vertical plate with a uniform temperature and thermal radiation, are analytically and graphically studied. Closed form solutions are determined for the dimensionless temperature and velocity fields, as well as the corresponding Nusselt number and skin friction coefficient. These solutions, presented in equivalent forms in terms of the Wright function or its fractional derivatives, have also been reduced to the known solutions of ordinary nanofluids. The influence of the fractional parameter on the temperature, velocity, Nusselt number, and skin friction coefficient is graphically underlined and discussed. The enhancement of heat transfer in the natural convection flows is lower for fractional nanofluids, in comparison to ordinary nanofluids. In both cases, the fluid temperature increases for increasing values of the nanoparticle volume fraction. The magnetohydrodynamic thin film nanofluid sprayed on a stretching cylinder with heat transfer is explored in [5]. The spray rate is a function of film size. Constant reference temperature is used for the motion past an expanding cylinder. The sundry behavior of the magnetic nano-liquid thin film is carefully noticed which results in to bring changes in the flow pattern and heat transfer. Water-based nanofluids like Al\({}_{2}\)O\({}_{3}\)-H\({}_{2}\)O and CuO-H\({}_{2}\)O are investigated under the consideration of thin film. The basic constitutive equations for the motion and transfer of heat of the nanofluidwith the boundary conditions have been converted to nonlinear coupled differential equations with physical conditions by employing appropriate similarity transformations. The modeled equations have been solved using homotopic approach and lead to detailed expressions for the velocity profile and temperature distribution. The pressure distribution and spray rate are also calculated. The residual errors show the authentication of the present work. The CuO-H\({}_{2}\)O nanofluid results from this study are compared with the experimental results reported in the literature and are found to have excellent agreement. The present work discusses the salient features of all the indispensable parameters of spray rate, velocity profile, temperature, and pressure distributions which have been displayed graphically and illustrated. In [6], the Brownian motion and thermophoresis effect of the liquid film flow over an unstable stretching surface in a porous space is presented. The main focus is on the variation in the thickness of the liquid film in a porous space. The graphical comparison of these two methods is elaborated. The physical and numerical results using h curves for the residuals of the velocity, temperature, and concentration profiles are obtained. The key observations concluded that higher values of porosity parameter generates larger open space and create hurdle to flow and as a result the flow field reduces. The larger values of Prandtl number reduces the thermal boundary layer due to which the temperature field reduces while the Eckert number is allied with the viscous dissipation term and lead to an increase the quantity of heat being produced by the shear forces in the fluid. Therefore, larger values of Eckert raise the temperature field. It is also seen that the larger values of thickness parameter transport more fluid in the boundary layer region and cooling effect is produced which absorbs the heat transfer from the sheet and, as a result, the temperature reduces. A radial basis function (RBF) neural network with three-layer feed forward architecture was developed in [7] to effectively predict the viscosity ratio of different ethylene glycol/water based nanofluids. A total of 216 experimental data involving CuO, TiO\({}_{2}\), SiO\({}_{2}\), and SiC nanoparticles were collected from the published literature to train and test the RBF neural network.