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An overview of heat transfer enhancement based upon nanoparticles influenced by induced magnetic field with slip condition via finite element strategy

Hafeez Muhammad B., Krawczuk Marek, Shahzad Hasan

Acta Mechanica et Automatica

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2022

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Vol. 16, no. 3

200--206

EN

The mathematical model of heat generation and dissipation during thermal energy transmission employing nanoparticles in a Newtonian medium is investigated. Dimensionless boundary layer equations with correlations for titanium dioxide, copper oxide, and aluminium oxide are solved by the finite element method. Parameters are varied to analyze their impact on the flow fields. Various numerical experiments are performed consecutively to explore the phenomenon of thermal performance of the combination fluid. A remarkable enhancement in thermal performance is noticed when solid structures are dispersed in the working fluid. The Biot number determines the convective nature of the boundary. When the Biot number is increased, the fluid temperature decreases significantly. Among copper oxide, aluminium oxide, and titanium oxide nanoparticles, copper oxide nanoparticles are found to be the most effective thermal enhancers.

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Unsteady mixed convection nonlinear radiative Casson nanofluid flow with convective boundary condition, heat source and inclined magnetic field effects

Unyong Bundit, Govindaraju Mathialagan, Gunasekaran Nallappan, Vadivel Rajarathinam

Journal of Applied Mathematics and Computational Mechanics

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2021

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Vol. 20, nr 3

65--76

EN

In this paper, we have studied the effect of heat source/sink on unsteady Casson nanofluid past a stretching surface with mixed convection inclined magnetic field and nonlinear thermal radiation numerically. Brownian and thermophoresis effects are studied in this nanofluid model (Buongiorno’s). The governing momentum, energy, and concentration equations are PDEs that are changed into ordinary differential equations by means of suitable transformations. The fourth-order R-K method with shooting technique is adapted to yield the results of this work. The velocity, thermal, and concentration profiles are discussed with the several physical parameters. Also, skin friction, the Nusselt number, and the Sherwood number are examined with the help of the table. It is found that the enhancing value of the unsteady parameter and heat sink parameters reduce the fluid temperature, and the enhancing value of the Casson parameter and heat source parameters increase the fluid temperature. The increasing value of the inclined magnetic field parameter enhances the thermal boundary layer thickness.

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Heat and mass transfer from a convectively heated vertical surface with chemical reaction and internal heat generation

Seini Ibrahim Yakubu

Engineering Transactions

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2019

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Vol. 67, iss. 1

101--118

EN

A numerical approach has been adopted to investigate the steady chemically mixed convection boundary layer flow from the right face of a vertical plate of finite thickness. Cold fluid flowing over the right face of the plate contains a heat generation that decays exponentially with a dimensionless distance from the surface. The left face of the plate is in contact with a hot flowing fluid. The heating process on that side is characterized by a convective boundary condition that takes into account the conduction resistance of the plate as well as a possible contact resistance between the hot fluid and the left face of the plate. Using a pseudo similarity approach, the governing equations for the mixed convective flow over the right face of the plate are transformed into a set of coupled ordinary differential equations which give local similarity solutions. The effects of local Grashof numbers (defined to represent a mixed convection parameter), Prandtl number, and the internal heat generation parameter on the velocity, temperature and concentration profiles are illustrated and interpreted in physical terms.

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Effects of heat source/sink and chemical reaction on MHD Maxwell nanofluid flow over a convectively heated exponentially stretching sheet using homotopy analysis method

Sravanthi C. S., Gorla R. S. R.

International Journal of Applied Mechanics and Engineering

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2018

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Vol. 23, no. 1

137--159

EN

The aim of this paper is to study the effects of chemical reaction and heat source/sink on a steady MHD (magnetohydrodynamic) two-dimensional mixed convective boundary layer flow of a Maxwell nanofluid over a porous exponentially stretching sheet in the presence of suction/blowing. Convective boundary conditions of temperature and nanoparticle concentration are employed in the formulation. Similarity transformations are used to convert the governing partial differential equations into non-linear ordinary differential equations. The resulting non-linear system has been solved analytically using an efficient technique, namely: the homotopy analysis method (HAM). Expressions for velocity, temperature and nanoparticle concentration fields are developed in series form. Convergence of the constructed solution is verified. A comparison is made with the available results in the literature and our results are in very good agreement with the known results. The obtained results are presented through graphs for several sets of values of the parameters and salient features of the solutions are analyzed. Numerical values of the local skin-friction, Nusselt number and nanoparticle Sherwood number are computed and analyzed.

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Entropy generation and squeezing flow past a Riga plate with Cattaneo-Christov heat flux

Atlas M., Hussain S., Sagheer M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2018

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Vol. 66, nr 3

291--300

EN

In this article, we investigate the convective heat transfer of the two-dimensional unsteady squeezing flow past a Riga plate. To examine the heat transfer, Cattaneo-Christov heat flux model is used. Influence of entropy generation on heat transfer has been investigated numerically. With the help of suitable similarity transformation, the governing partial differential equations (PDEs) are converted into ordinary differential equations (ODEs). The obtained system of non-linear ordinary differential equations subject to the convective boundary conditions is solved by the shooting method using the computational software MATLAB. To strengthen the reliability of the results obtained by the shooting method, the MATLAB built-in function bvp4c has been used. The graphs show the effect of different physical parameters for velocity, temperature, concentration and tables are presented to observe the behaviour of skin friction and sherwood number under the influence of certain physical parameters. It is observed that for increasing values of thermal relaxation parameter, the temperature profile increases and an opposite behaviour is shown for the concentration profile. Moreover, with an increase in the Brinkman number, the entropy generation increases.