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Hybrid nanofluid is a novel nanotechnology fluid created by distributing two distinct nanoparticles into conventional energy transfer fluid. The thermal properties of aluminum alloys, namely AA7072 and AA7075 with engine oil (base fluid) of hybrid nanofluid flow induced over a vertical stretchable rotating cylinder are investigated in this study. The focus here is the analysis of energy transportation in the presence of Joule heating, thermal energy source/sink, thermal radiation and activation energy. Moreover, all energy constraints are analyzed through graphical outcomes, which are computed numerically through bvp4c built-in MATLAB. The significant observation made is that as the Reynolds number and the magnetic field parameter enhance, the flow field declines. Additionally, the convective transport of the thermal energy increases for a higher magnitude of resistive heating and buoyant motion of the fluid. It is also noted that the activation energy in the system decreases for mass diffusion.

The heat and mass transfer in normal impingement of the Hiemenz stagnation-point flow of a viscous nanofluid on a bidirectional stretching sheet under the influence of the magnetic field is investigated. In a recent study, Weidman (Meccanica, vol. 53, p.833, 2018) has analyzed the phenomenon of the Hiemenz stagnation-point flow over the biaxially stretching sheet. Dual solutions have been found in this study for the various values of $\alpha$ (streamwise stretching rate) and $\beta$ (cross-stream stretching rate). In the present work, the mechanism of thermal and solutal energy transport in the Hiemenz stagnation-point flow of nanoliquid is studied in the view of thermophoretic and Brownian forces. The solutions of similar ordinary differential equations (ODEs) for flow and energy transport in viscous nanofluid are computed with help of bvp4c numerical technique. The impact of dimensionless parameters on flow field and energy transport is presented graphically and discussed with physical reasoning. The outcomes reveal that the higher magnitude of Lorentz force declines the flow field in cross-stream and vertical directions, but conflicting behavior is noted for streamwise velocity component in the case of $\alpha <1$ and $\alpha >1$. Both thermophoresis and Brownian motion of nanoparticles enhance the energy transport in Hiemenz flow of viscous fluid. The results of the present study are validated through the shear stress parameters with a previously published study.

This paper discusses the impacts of velocity, temperature, and solutal slip on the mass and heat transfer characterization of MHD mixed convection Casson fluid flow along an exponential permeable stretching surface with chemical reaction, Dufour and Soret effects. The Casson fluid is supposed to flow across an exponentially stretched sheet, together with the exponential temperature and concentration fluctuations of the fluid. As governing equations, the momentum, energy and species concentration equations are constructed and represented as PDEs. Following that, these equations were converted via the similarity transformation into ODEs. Finally, the ODEs are numerically solved using the Keller-box method with MATLAB software’s algorithm. Expressions are produced for the fluid flow, temperature and concentration gradients. We also determined the physical variables from which the friction factor, rate of mass and heat transfer are attained for engineering purposes. Using graphs and tables, the impacts of altered physical characteristics on flow amounts are explored. The consistency and validity of our outcomes revealed a significant degree of agreement when comparing them to previously published studies. The findings reveal that raising the Soret and Dufour parameter enhances the velocity profile at the wall, but the converse is true for increasing the velocity slip factor.

This study intends to examine the consequences of the externally applied magnetic field and modified Hall effect on nanofluid flow across two symmetrically spinning and extending discs, where continuously the upper disc moves upward and downward. The lower disc is vertically fixed. The discs rotate and move vertically, generating a 3D flow. The mass density, heat transfer and flow motion have been evaluated and modeled in the form of the system of partial differential equations (PDEs) with an additional influence of activation energy, heat source and chemical reaction. The system of PDEs is modified to an ordinary set of differential equations by employing the resemblance substitution method. The obtained system of ODEs is further solved through the numerical approach (bvp4c). The results are compared to the bvp4c package and published work for validity purposes. In the case of downward displacement of the upper disc, magnetic and Hall characteristics have a significant impact on the velocity curve. The energy curve elevates with the upward movement of the disc, while it reduces with the downward fluctuation. Furthermore, the mass transmission rate enhances with the influence of hall current, while diminishing with the impact of chemical reaction rate.

Cancer is one of the universal popular healthcare problems, and there is a struggle to find advanced fresh medicines andidentify superior ways of distributing medications. Cancer is harmful and deadly to maximum of its patients. Cytotoxic agents are carried by cancer cells, to increase efficacy and protection. This reminds us that nanotechnology can be utilized for medicine. This current allegation has built into gold nanomaterials which could conquer and heal — it being the material considered like gold (atomic number 79). It gives a large amount of heat and contributes to the therapy of malignant tumors. Therefore, it is urgent to investigate the flow of blood-based gold nanoparticles over the porous medium for injection/suction effects. Time-dependent viscosity was used in Reynolds exponential model. The existence of magnetic field and nonlinear thermal radiation was integrated into the system. Ensuing equations were interpreted by its nondimensional model by applying comparison renovation. This Lobatto IIIA formula (known as bvp4c) was working to acquire multiple solutions. This findings indicate that temperature increases due to magnetic and radiation effects. Temperature and velocity profiles by injection are greater although related to the suction phenomenon. Further, the temperature and velocity augment by the inclusion of gold nanoparticles into blood flow.

This novel study unfolds the heat and mass transfer investigation of Williamson nanofluid (WNF) through a porous medium past a stretching plate, along with considering heat generation/absorption. Nanoparticles hold significant significance in thermal engineering, industrial operations, and biomedical advancements, contributing to enhanced heat transfer, cooling mechanisms, thermal extrusion processes, and applications in cancer treatment, particularly in addressing brain tumors. The coupled ordinary differential equations (ODEs) are gained from governing partial differential equations (PDEs) by applying sufficient transformations. Then the ODEs of a nonlinear nature, along with boundary conditions, are solved through bvp4c, a built-in MATLAB program. A good agreement has been found in comparing the present study with already published papers. Numerical values for skin friction, mass transfer, and heat transfer are shown through a table against involved physical parameters, especially for both injection $(S<0)$ and suction $(S>0)$ cases, by varying the values of unsteadiness parameter A and Weissenberg number $W_e$. The effects of the physical parameters on velocity, temperature, and mass profile are graphically depicted and illustrated minutely. It is noted that both the magnetic and Williamson parameters cause the thickness of the boundary layer to be reduced. It can be deduced from these findings that the rate of heat transfer over the surface of the plate decreases as the unsteadiness parameter increases. Furthermore, it is observed that an increase in the parameters of thermophoresis and Brownian motion leads to a higher temperature of the nanofluid.

This paper aims at developing non-similar solutions for heat transfer augmentation in ternary hybrid nanofluids. Nanofluid is composed of three distinct (Silver, Copper, Aluminum oxide) nanosize particles while water is considered as a base fluid. Darcy–Forchheimer expression with variable porosity and permeability is adopted. Joule heating and viscous dissipations are also considered. Non-similar approach is utilized. Numerical solutions are computed by bvp4c solver of MATLAB. Graphical illustrations for flow and thermal fields behavior are provided. Comparative results are obtained for ternary hybrid nanofluid and nanoliquid. Physical quantities such as skin drag coefficient and Nusselt number are computed and interpreted. Our results reveal that rate of heat transfer augments substantially for Ag/water nanofluid in comparison to other classes of nanofluid.