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The size of nanoparticles influences the viscosity and thermal conductivity of a nanofluid flow. In this exploration, the impacts of the dynamic viscosity and thermal conductivity of the Corcione model on the magneto-hydrodynamics (MHD) Cu-water nanofluid flow over an exponentially stretched surface are examined. It is pertinent to mention that the whole scenario is done at 300 K and the freezing temperatures of 273.15 K with a particle size of 25 nm. The Navier slip and convective boundary conditions are assumed at the surface. A homogeneous single-phase model is adopted to formulate the problem. Nonlinear, coupled momentum, and energy balance nondimensionalized ordinary differential equations (ODEs) are constructed with suitable transformations. To solve these ODEs numerically, a renowned bvp4c technique of MATLAB software is employed. The effects of the arising parameters are represented graphically and numerically and are depicted in tables and graphs. It is witnessed that the velocity of the copper-water nanofluid declined with larger estimations of the volume fraction of nanoparticles, although the temperature distribution showed the reverse tendency. Moreover, at the surface for higher values of the slip parameter, the velocity profile reduces and the temperature of the fluid augments for higher values of the Biot number. The validation of the model is also executed by comparing it with the published result in the limiting case. An outstanding correlation is attained. [ABSTRACT FROM AUTHOR]

This research aims to examine the combined effects of Cattaneo–Christov heat flux and heat generation/absorption on magnetohydrodynamic (MHD) nanoliquid (Fe3O4-Ethylene glycol) across a linearly stretchable bidirectional surface immersed in a permeable media. The characteristics of nanoliquid (viscosity and thermal conductivity) are a function of temperature and nanoparticle volume fraction. The problem is formulated by considering Corcione's correlation which describes the effective viscosity and thermal conductivity of nanoliquid. The application of Corcione's correlation on a bidirectional surface with a combination of MHD nanofluid comprising the unique combination of (Fe3O4-Ethylene glycol) makes this idea novel and is being presented for the first time. The implementation of appropriate similarity transformation leads to the transition of coupled momentum and energy equations into dimensionless ordinary differential equations (ODEs). These ODEs are numerically addressed by applying a well-known bvp4c method in MATLAB. The outcome of the arising parameters on the velocity and thermal field of nanoliquid are demonstrated graphically and numerically (drag force coefficient and Nusselt number) depicted through tables. It is observed that the porosity and velocity slip parameters combined with the volume fraction of nanoparticles decay velocity field. It is also comprehended that heat transmission augments by escalating the volume fraction of nanoparticles. A strong correlation is reflected in comparing the findings of the current analysis with the preceding literature. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) are nanoscale tubes made of carbon atoms with unique mechanical, electrical, and thermal properties. They have a variety of promising applications in electronics, energy storage, and composite materials and are found as single-wall carbon nanotubes (SWCNTs) and double-wall carbon nanotubes (DWCNTs). Considering such alluring attributes of nanotubes, the motive of the presented flow model is to compare the thermal performance of magnetohydrodynamic (MHD) mono (SWCNTs)/Ethylene glycol) and hybrid (DWCNTs- SWCNTs/Ethylene glycol) nanofluids over a bidirectional stretching surface. The thermal efficiency of the proposed model is gauged while considering the effects of Cattaneo-Christov heat flux with prescribed heat flux (PHF) and prescribed surface temperature (PST). The flow is assisted by the anisotropic slip at the boundary of the surface. The system of partial differential equations (PDEs) is converted into a nonlinear ordinary differential system by the use of similarity transformations and handled using the bvp4c numerical technique. To depict the relationship between the profiles and the parameters, graphs, and tables are illustrated. The significant outcome revealed that the fluid temperature rises in the scenario of both PST and PHF cases. In addition, the heat transfer efficiency of the hybrid nanoliquid is far ahead of the nanofluid flow. The truthfulness of the envisioned model in the limiting scenario is also given. [ABSTRACT FROM AUTHOR]

The objective of this study is to illustrate the influence of Marangoni convection, nonlinear heat sink/source, thermal radiation, viscous dissipation, activation energy, Soret and Dufour effects on magnetohydrodynamics flow of nanofluid generated by rotating disk. Further, the entropy generation equation is derived as a function of velocity, concentration, and thermal gradients. The governing equations of the model along with associated boundary constraints are reduced to ordinary differential equations by adopting suitable similarity transformation. Later, these equations are tackled numerically by means of shooting technique. The whole examination is performed by using two distinctive nanoparticles of ferrites in particular, manganese zinc ferrite (MnZnFe2O4) and nickel zinc ferrite (NiZnFe2O4) in a carrier liquid ( C 1 0 H 2 2). The physical characteristics of velocity, thermal, concentration entropy generation, skin friction, and Nusselt number against numerous pertinent parameters are discussed in detail and deliberated graphically. Result reveals that thermal gradient shows substantial enhancement for advanced values of heat sink/source parameter. The entropy production increases with an augmentation in the Brinkman number and Marangoni ratio values. The escalation in Marangoni ratio and Dufour number improves the rate of heat transference. [ABSTRACT FROM AUTHOR]

• The buoyant characteristics of a fluid can be considerably changed by the addition of nanoparticles. • The stream velocity is going to increase as it approaches the stretching velocity, as well as the velocity at the stagnation point. • The magnetic field is helpful for the increasing Sherwood number, while the buoyancy forces help to decrease it for the stretching sheets. • Prandtl and Lewis numbers phenomenon has significant implications for various industrial processes, such as chemical reactions and heat transfer. • Nonlinear nanofluid flow model is significant for the optimization of heat transfer systems which are utilized in a variety of technical applications. This study aims to examine the buoyancy features of the magnetohydrodynamic (MHD) stagnation point flow and temperature transfer in a nanofluid flow through a convectively heated stretching sheet. The dimensionless form of the governing model is highly nonlinear ordinary differential equations (ODEs) and solved using the Homotopy Analysis Method (HAM). To obtain series solutions the computational program MATHEMATICA is used. It is found that the fluid velocity and boundary layer thickness decrease when the velocity of the stretching sheet is less than the free fluid velocity. The stretching parameter λ and the buoyancy ratio Nr reflect an increase in the velocity profile f′(η) and a decline in the temperature θ (η) and the concentration profile ϕ (η). The skin friction C f increases because of the motion of nanoparticles and the Nusselt numbers Nu x , reduce with the magnetic parameters and increase with the convective parameters. Increased in the Prandtl, Pr, and Lewis numbers, Le values indicated a faster heat transfer to mass transfer. Additionally, results show that the magnetic field accelerates the mass transfer and enhances fluid flow, leading to a higher Sherwood number (Sh x). [ABSTRACT FROM AUTHOR]

The assessment of non-Newtonian fluids has fascinated much research interest over the last few decenniums. The investigations of these liquids are promoted by their applications in manufacturing areas like plastic thawing, material dispensation, polymeric liquids, nuclear plants and toxin, biochemical engineering, pharma product, mechanical applications and food industry. In this work, we have addressed the significance of bioconvection analysis for magnetized Tangent Hyperbolic nanofluid capturing features of gyrotactic moment of microorganisms and radiation phenomenon. The impacts of MHD are deliberated in momentum equation whereas in energy equation the aspects of thermal radiation are studied. We familiarized the chemical reaction term in concentration equation for convalescing the mass transfer. Since, our governing equations appear in form of partial differential equations. These partial differential equations are nonlinear, by using suitable similarity transformations these equations can be converted into ordinary differential equations. To obtained numerical solution, the simplified mathematical framework can be processed by using the Bvp4c a MATLAB program. The physical nature can be disclosed by computation of heat transfer rate, mass transfer rate, density of microbe for temperature, concentration as well as microorganism respectively. The thermophoresis parameter boosts for both temperature and concentration profile, while Brownian motion parameter has a contradicting tendency for temperature and concentration profile. The magnetic parameter and power law index parameter have opposite behaviour for the microorganism profile. This research analysis has numerous applications in biomedical engineering, biomechanics, food factories, heat control systems, thermal exchangers and aero dynamical systems. [ABSTRACT FROM AUTHOR]

Power law rheological model is used for mathematical modeling of simultaneous transport of heat and energy via hybrid nanoparticles distributed in heat generating fluid exposed to magnetic field. Governing conservation laws, correlation between thermos-physical properties fluid, solid particles, suitable no-slip momentum and temperature boundary conditions are provided system of boundary value problems which are solved numerically using finite element method (FEM). The FEM simulations are used in capturing the dynamics of physical parameters on the momentum transport and heat energy transfer under the influence of non-uniformly moving surface which is being heated in non-uniform manner. Power law fluid flow experiences retardation as intensity of magnetic field is increased. Hybrid nanofluid is more heat generative than mono nanofluid and power law index causes a decrease in flow. Consequently, convective transport of heat is compromised. Generative and destructive chemical reactions have opposite trend on transport of species in power law fluid. [ABSTRACT FROM AUTHOR]