In this study, forced convection heat transfer of non-NEWTONIAN NANOFLUIDs in a horizontal tube with constant wall temperature under turbulent flow conditions was investigated using computational fluid dynamics tools. For this purpose, non-NEWTONIAN NANOFLUIDs containing three types of nanoparticles (Al2O3, TiO2 and CuO) with carboxymethylcellulose aqueous solution as a liquid single phase with three average particle sizes of 10, 25 and 40 nm NANOFLUIDs were investigated. Effects of nanoparticle type and Peclet number on the convective heat transfer coefficient were investigated in fully turbulent region of a horizontal tube. A correlated equation was obtained for Nusselt number using the dimensionless numbers by applying the simulation results. Results showed that the correlated data were in very good agreement with the experimental ones obtained from the literature. The maximum error was 12%.

Two dimensional steady hydromagnetic boundary layer flow of a viscous, incompressible, and electrically conducting NANOFLUID past a stretching sheet with NEWTONIAN heating, in the presence of viscous and Joule dissipations is studied. The transport equations include the combined effects of Brownian motion and thermophoresis. The governing nonlinear partial differential equations are transformed to a set of nonlinear ordinary differential equations which are then solved using Spectral Relaxation Method (SRM) and the results are validated by comparison with numerical approximations obtained using the Matlab in-built boundary value problem solver bvp4c, and with existing results available in literature. Numerical values of fluid velocity, fluid temperature and species concentration are displayed graphically versus boundary layer coordinate for various values of pertinent flow parameters whereas those of skin friction, rate of heat transfer and rate of mass transfer at the plate are presented in tabular form for various values of pertinent flow parameters. Such NANOFLUID flows are useful in many applications in heat transfer, including microelectronics, fuel cells, pharmaceutical processes, and hybrid-powered engines, engine cooling/vehicle thermal management, domestic refrigerator, chiller, heat exchanger, in grinding, machining and in boiler flue gas temperature reduction.

Microfluidic technology and Micro Electromechanical Systems (MEMS) have received much attention in science and engineering fields over the last few years. MEMS can be found in many areas like heat exchangers, chemical separation devices, bio-chemical analysis and micro pumps. Keeping these facts in mind, the prime purpose of the current paper is to present the flow of Carreau NANOFLUIDs through the micro-channel with the electro-osmosis, Joule heating and chemical reactions. The effect of external magnetic field is also considered into account. For the formulation of the problem, the Cartesian coordinate system is considered. The perturbed solutions have been presented by making use of regular perturbation method. The graphical results also prepared corresponding to numerous values of fluid flow phenomenon like velocity, temperature, solutal nano-particle concentration, Sherwood number and Nusselt number with different fluid variables. It is concluded from our analysis that; velocity decrement is identified with respect to the enhancing the magnetic parameter (Hartmann number). The Schmidt number, Radiation term, Prandtl number and chemical reaction term increase the solutal nano-particle concentration. The outcomes of the NEWTONIAN liquid model can be obtained from our scrutiny. The present scrutiny has many applications in engineering sciences such as electromagnetic micro pumps and nano-mechanics.

Single and multi-walled carbon nanotubes (SWCNTs & MWCNTs) comprise a large group of nanometer-thin hollow fibrous nanomaterials having physico-chemical characteristics like atomic configuration, length to diameter ratios, defects, impurities and functionalization. This manuscript is devoted for the analysis of carbon nanotubes based non-NEWTONIAN NANOFLUID suspended in ethylene glycol taken as base fluid. The problem is modeled through modern method of fractional calculus namely Atangana-Baleanu fractional derivative and then solved analytically by invoking Laplace transform. The analytic solutions are established for the temperature and velocity distribution and expressed in terms of special function. The graphical results are depicted through computational software Mathcad and discussed for carbon nanotubes with various embedded parameters. An interesting comparison is explored graphically between single and multi-walled carbon nanotubes subject to the single and multi-walled carbon nanotubes are suspended in ethylene glycol. The several similarities and differences suggested that carbon nanotubes are accelerated and decelerated, while for unit time t = 1s, carbon nanotubes have identical velocities with and without fractional approach.

The motivation of the current work is the flow over a slender surface, which includes the manufacture of optical fibers, polymer sheets, photoelectric devices, wire coatings, solar cells, and fiber sheets. In order to enhance the results of the wire coating process, it is necessary to carefully examine the mass and thermal heat transmission rates. The novelty of this study is the ability to forecast complex thermal issues in the tri-hybrid Sutterby NANOFLUID flow, considering the effects of electro-hydromagnetic and multi-slip circumstances. The study examines the impact of nonlinear thermal radiation, electric field, and slips in velocity, temperature, and solutal properties on the steady flow confined to two-dimensions Au-TiO2-GO/SA in the field of electro-magneto-hydrodynamics.   Employing similarity transformations, the regulatory boundary layer equations are converted to nonlinear ODEs. Following that, the resulting equations are solved using the homotopy perturbation method. Numerical simulations are performed for several physical parameter values, and the influences of numerous distributions are examined. It is observed that the thermal distribution exhibits a decreasing trend as the values of the mixed convection flow, electric field, temperature jump, and velocity slip parameters are boosted. Moreover, the Sherwood number is declining by m, De, δ1, δ2, and δ3 and rising due to the enhancement of E1, γ1, and γ3.

The problem of convective heat transfers of Eyring-Powell conveying Copper (Cu) coupled with alumina (Al2O3) are employed as the combination of particles, along with water as the base fluid over a vertical Riga plate is numerically addressed. The performance of heat transmission is influenced by the electromagnetohydrodynamic (EMHD) imposed produced from the Riga plate, and it could be used to postpone boundary layer separation. A model in the form of Partial Differential Equations (PDEs) is introduced to describe the physical behavior of the proposed problem. With the inclusion of relevant equation variables, this collection of PDEs is transformed into Ordinary Differential Equations (ODEs) which are in a less complex form. Then the bvp4c solver was employed to solve the respective equations. The characteristics of fluid velocity and temperature are investigated graphically. It is found the buoyancy assisting and opposing flows offered dual solutions whereas the purely forced convection flow gives a unique solution. Through an investigation of flow stability, the first solution is confirmed as the physical one. In essence, the volumetric concentration of Cu increases the heat-transferring ability for assisting and opposing flows. The higher suction imposed at the boundary causes a decrease in the heat transfer rate under the shrinking case.

In this research, the thermal and hydrodynamic behavior of a non-NEWTONIAN NANOFLUID turbulent flow in the counterflow arrangement in a double pipe helical heat exchanger is numerically simulated. A solution of carboxymethyl cellulose powder in water with a mass percentage of 0.1% with a nanoparticle of aluminum oxide as a working fluid has been used. The computational fluid dynamics commercial software Fluent was used to solve the governing equations, the results were in a good agreement with experimental data. The effect of important parameters such as curvature, Reynolds number and volume percentage of aluminum oxide nanoparticles on the heat transfer has been investigated. The results show that as the curvature ratio increases in constant Dean (Dn) numbers, the Nu number and the coefficient of friction increase. The addition of nanoparticles of aluminum oxide to the base fluid for the flow with the constant Reynolds and Dn number increases the heat transfer and increases the pressure drop in the helically coiled tubes. The centrifugal force generated by the curvature of the coiled tubes results in a secondary flow in the heat exchanger so that the heat transfer and pressure drop increased up to 35% and 30%, respectively, compared to the straight tubes. The effect of heat transfer enhancement methods on the hydrodynamic index has also been studied, so that in the helical coils, the amount of hydrodynamic index increased with decreasing curvature ratio and increasing the volume concentration of nanoparticles.

Neural networks are powerful tools for evaluating the thermophysical characteristics of NANOFLUIDs to reduce the cost and time of experiments. Dynamic viscosity is an important property in NANOFLUIDs that usually needs to be accurately computed in heat transfer and NANOFLUID flow problems. In this paper, the rheological properties of NANOFLUID phase change material containing mesoporous silica nanoparticles are predicted by the artificial neural networks (ANNs) method based on the experimental database reported in literature. Experimental inputs include nanoparticle mass fractions (0-5 wt.%), temperatures (35-55℃), and shear rates (10-200 s-1), and targets include dynamic viscosities and shear stresses. A multilayer perceptron feedforward neural network with Levenberg-Marquardt back-propagation training algorithm is utilized to predict rheological properties. The optimal network architecture consists of 22 neurons in the hidden layer based on the minimum mean square error (MSE). The results showed that the developed ANN has an MSE of 6.67×10-4 and 6.55×10-3 for the training and test dataset, respectively. The predicted dynamic viscosity and shear stress also have the maximum relative error of 6.26% and 0.418%, respectively.

The problem of steady, laminar, mixed convection flow of a non-NEWTONIAN fluid past a preamble vertical flat plate embedded in a porous medium saturated with a NANOFLUID is considered. A mixed convection parameter for the entire range of free-forced-mixed convection is employed and a set of non-similar equations are obtained. These equations are solved numerically by an efficient implicit, iterative, finite-difference method. The obtained results are checked against previously published work for special cases of the problem and are found to be in good agreement. A parametric study illustrating the influence of the various physical parameters on the velocity, temperature and nano-particle volume fraction profiles as well as the local Nusselt and Sherwood numbers is conducted. The obtained results are illustrated graphically and the physical aspects of the problem are discussed.

In this article, the ways where thermal radiation, besides other sources of heat, influence the magnetohydrodynamic stream of a Jeffery NANOFLUID across a widening sheet is investigated. To recover the accuracy of the NANOFLUID model, the effects of viscous indulgence, chemical response, Brownian motion, and thermophoresis have all been incorporated. The mathematical model of this system is first determined in PDEs format and then turned into ODEs format by similarity process. The numerical simulation of the ensuing nonlinear ODEs with subsequent periphery conditions is established by employing the Runge-Kutta fourth-order integration scheme with the shooting technique. The role of various stream considerations on stream, temperature, nanoparticle concentration, skin friction coefficient, Nusselt and Sherwood quantities are conveyed and explored in graphs and tables. In a limiting sense, the legitimacy of computational outcomes is assessed by comparing them to previously published data. The stream distribution quickens as the Deborah quantity accumulates, whereas the temperature and concentration profiles reflect the downward pattern.