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1

Entropy generation analysis of MHD micropolar – nanofluid flow over a moved and permeable vertical plate

Mesbah Abderaouf, Allouaoui Reda, Bouaziz Amina Manal, Bouaziz Mohamed Najib

International Journal of Applied Mechanics and Engineering

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2024

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Vol. 29, no. 1

73--89

EN

The work's goal is to learn more about how a magnetic field, Brownian motion, and thermophoresis diffusion influence convective heat transfer in a micropolar-nanofluid flow's laminar boundary layer. Near a vertically moving, permeable plate, the complex fluid is subjected to MHD. The MATLAB application bvp4c was utilized to simplify the governing nonlinear and coupled equations for the micropolar-nanofluid, leading to the solution of the ensuing ordinary differential equations (ODEs). Graphs have been used to analyze the effect of different relevant active factors on the flow field and temperature. The results demonstrate that the micro-rotation of the nanoparticles taken into account and in suspension becomes significant for the complex fluid in the presence of the magnetic field. Analysis of the generation entropy shows that the surface is a significant source of irreversibility. There is no discernible effect of micropolarity on the relationship between Brownian and thermophoresis numbers and entropy generation.

2

Effects of variable fluid properties and mixed convection on biomagnetic fluid flow and heat transfer over a stretching sheet in the presence of magnetic dipole

Murtaza M. G., Alam Jahangir, Tzirtzilakis E. E., Shamshuddin Md., Ferdows M.

Journal of Power Technologies

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2023

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Vol. 103, nr 4

193--208

EN

This investigations covers the numerical analysis of a steady biomagnetic fluid flow (BFD) that passed through a two dimensional stretching sheet under the influence of magnetic dipole. The effect of fluid variable viscosity and thermal conductivity are also taken into consideration as assumed to vary as linear function of temperature. Our model mathematically formulated for BFD namely blood which consist of principles of magnetohydrodynamic (MHD) and ferrohydrodynamic (FHD), where blood treated as an electrically conducting fluid as well as polarization. Using similarity transformations, the governing system of partial differential equations are transferred into system of ordinary differential equations (ODE). The resulting coupled non linear ODE is numerically solved by employing bvp4c function technique available in MATLAB software. The effects of pertinent parameters namely ferromagnetic interaction parameter, magnetic field parameter, mixed convection parameter, viscosity variation parameter, Prandtl number, thermal conductivity parameter etc are plotted and discussed adequately for velocity and temperature profile as well as skin friction coefficient and rate of heat transfer. The results revels that velocity profile decreases as enhanced values of ferromagnetic number whereas temperature profile increased. Also found that skin friction coefficient reduces and rate of heat transfer increases by increasing values of thermal conductivity parameter and viscosity variation parameter. For numerical validation a comparisons has been made for some specific values with previous investigators. We hope that the present analysis will present in bio-medical and bio-engineering sciences.

3

Numerical study of a transient MHD flow across an oscillating vertical plate with thermal radiation and viscous dissipation

Rajaraman R., Muthucumaraswamy R.

International Journal of Applied Mechanics and Engineering

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2023

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Vol. 28, no. 2

77--89

EN

The flow of an electrically conducting fluid across a vertically positioned oscillating semi-boundless plate with uniform mass diffusion and temperature is examined in this study in terms of the effects of thermal radiation and viscous dissipation. The dimensionless governing equations were solved using an effective and unconditionally stable implicit finite-difference approach known as the Crank-Nicolson method. Based on the numerical results, the impacts of various physical parameter values on concentration, temperature; velocity; Sherwood numbers, Nusselt numbers and skin-friction profiles are displayed graphically and their consequences thoroughly analyzed. We observed that when the magnetic field, radiation and phase angle parameters are increased, the velocity is reduced. This shows that plate oscillation, radiation and magnetic fields affect the flow pattern significantly.

4

Magnetohydrodynamic flow around an elongated cylinder in non-Darcian porous regime with higher order chemical reaction and Soret/Dufour effects

Das Utpal Jyoti, Begum Jubi

International Journal of Applied Mechanics and Engineering

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2023

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Vol. 28, no. 1

11--22

EN

Here, we consider magnetohydrodynamic flow of an incompressible, time independent fluid past an elongated cylinder surrounded in a non-Darcian porous regime with magnetic flux supplied at an acute angle. The Soret/Dufour effects and the higher order chemical reactions are also included in the present study. The subsequent governing equations are resolved using the MATLAB-bvp4c method. The flow velocity appears to decrease with the growth of the Reynolds number, inertia parameter, magnetic field and angle of inclination of the magnetic flux, but improves with the Darcy number. The inertia parameter enhances the fluid temperature and skin friction. Further order of chemical reaction, Soret/ Dufour number plays a significant role in the system.

5

An unsteady electro-magnetohydrodynamic two-liquid plasma flow along a channel of insulating porous plates with Hall currents

Rao V. Gowri Sankara, Raju T. Linga

International Journal of Applied Mechanics and Engineering

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2023

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Vol. 28, no. 2

90--112

EN

It is proposed to use the Hall currents to model the transient magneto-hydrodynamic two liquid flows and heat transfer of ionized gases propelled by a common pressure gradient via a horizontal channel consisting of parallel porous plates. For the distributions of velocity and temperature, the principal partial differential equations that explain heat transfer flow under the chosen constraints are resolved. Graphical representations are given for the distributions of velocity, temperature, and heat transfer rates. This research will be carried out using non-conducting porous plate’s channel.

6

Substrates with different magnetic properties versus iron-nickel film electrodeposition

Białostocka Anna M., Klekotka Marcin, Klekotka Urszula, Żabiński Piotr R., Kalska-Szostko Beata

Chemistry-Didactics-Ecology-Metrology

|

2023

|

R. 28, NR 1-2

157--170

EN

The hereby work presents the iron-nickel alloys electroplated on the different metallic substrates (aluminium, silver, brass) using galvanostatic deposition, with and without presence of the external magnetic field (EMF). The films were obtained in the same electrochemical bath composition - mixture of iron and nickel sulphates (without presence of additives) in the molar ratio of 2 : 1 (Ni : Fe), the electric current density (50.0 mA/cm2), and the time (3600 s). The mutual alignment of the electric (E) and magnetic field (B) was changeable - parallel and perpendicular. The source of EMF was a set of two permanent magnets (magnetic field strength ranged from 80 mT to 400 mT). It was analysed the surface microstructure, composition, morphology, thickness and the mechanical properties (roughness, work of adhesion). The surface morphology and the thickness of films were observed by Scanning Electron Microscopy (SEM) and Confocal Laser Scanning Microscopy (CLSM). The elemental composition of all FeNi films was measured using Wavelength Dispersive X-Ray Fluorescence (WDXRF). The crystalographic analysis of the deposits was carried out by X-Ray Diffraction. Depending on the used substrate, modified external magnetic field orientation influenced the tribological and physio-chemical properties of the deposited layers. The diamagnetic substrates and EMF application reduced the FeNi thickness and the average crystallites size, in contrast to the paramagnetic substrate. Parallel EMF increased the value of the tribological parameters for CuZn and Ag but decreased for Al. The content of FeNi structure was rising in the case of diamagnetic substrate and the dependence was opposite on the paramagnetic substrate.

7

Newtonian heating effect on heat absorbing unsteady MHD radiating and chemically reacting free convection flow past an oscillating vertical porous plate

Prabhakar Reddy B., Makinde O. D.

International Journal of Applied Mechanics and Engineering

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2022

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Vol. 27, no. 1

168--187

EN

In this article, we have discussed in detail the effect of Newtonian heating on MHD unsteady free convection boundary layer flow past an oscillating vertical porous plate embedded in a porous medium with thermal radiation, chemical reaction and heat absorption. The governing PDEs of the model together with related initial and boundary conditions have been solved numerically by the finite element method. The dimensionless velocity, temperature and concentration profiles are analyzed graphically due to the effects of key parameters in the concerned model problem. Computed results for the skin friction coefficient, Nusselt number and Sherwood number are put in tabular form. It is observed that the thermal and mass buoyancy effects support the velocity whilst a reverse effect is noticed when the strength of the magnetic field is increased. The velocity and temperature enhances with an increase in the Newtonian heating and thermal radiation whilst a reverse effect is observed with an increase in the Prandtl number and heat absorption parameter. Increasing Schmidt number and chemical reaction parameter tends to depreciate both velocity and concentration. The Newtonian heating, thermal radiation and magnetic field tends to decrease in the skin friction. The Nusselt number increases with increasing Newtonian heating and heat absorption parameters. An increase in the Schmidt number and chemical reaction rate tends to improve the Sherwood number.

8

MHD free convective heat and mass transfer flow from a vertical porous surface with variable thermal conductivity, variable mass diffusivity and thermal diffusion including viscous dissipation and chemical reaction

Phakirappa J., Priyanka S., Veena P. H., Pravin V. K.

International Journal of Applied Mechanics and Engineering

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2022

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Vol. 27, no. 3

127--136

EN

analysis is carried out to study chemically reactive, viscous dissipative effects of an incompressible and electrically conducting fluid with MHD free convection adjacent to a vertical surface with variable thermal conductivity (VTD) and variable mass diffusivity (VMD). An approximate numerical solution for the steady laminar boundary layer flow over a wall of the surface in the presence of species concentration and thermal mass diffusion has been studied. Using numerical techniques the governing boundary layer equations are solved to get the exact solution. Numerical calculations are carried out for different values of dimensionless parameters. The results are exhibited through various graphs and it is observed from the analysis of the results that the velocity field is appreciably influenced by the magnetic effect, porous effect, chemical reaction and buoyancy ratio between the species and thermal diffusion at the wall of the surface.

9

Effect of MHD on unsteady oscillatory Couette flow through porous media

Sharma Bhupendra K., Sharma Pawan Kumar, Cauhan Sudhir Kumar

International Journal of Applied Mechanics and Engineering

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2022

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Vol. 27, no. 1

188--202

EN

This paper describes the effects of a magnetic field on unsteady free convection oscillatory systems. When temperature and species concentration fluctuate with time around a non-zero constant, "Couette flow" across a porous medium occurs. The system of non-linear ODEs that governs the flow is solved analytically using the perturbation approach because the amplitude of fluctuations is very tiny. Mean flow and transient velocity, transient concentration, transient temperature, heat transfer, mean skin friction and phase and amplitude of skin friction. All have approximate solutions. The influence of different parameters on flow characteristics has been specified and discussed.

10

Chemical reaction and MHD flow for magnetic field effect on heat and mass transfer of fluid flow through a porous medium onto a moving vertical plate

Goud B. Shankar, Nandeppanavar Mahantesh M.

International Journal of Applied Mechanics and Engineering

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2022

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Vol. 27, no. 2

226--244

EN

This article discusses the effect of heat and mass transfer in a boundary layer flow in the presence of a magnetic field of an electrically conducting and viscous fluid as it passes through a porous medium containing a heat source and a chemical reaction. By employing similarity variables, the governing equations are changed into nonlinear ordinary differential equations(ODEs). To solve the obtained equations numerically the Keller box method is used. Numerical and graphical representations of the results of different parameter values governing the flow system are given. The non-dimensional distributions of velocity, heat, and concentration are depicted graphically, while the Nusselt number, Sherwood number, and skin friction are determined numerically.

11

Wavelet-based numerical solution for MHD boundary-layer flow due to stretching sheet

Karkera Harinakshi, Katagi Nagaraj N.

International Journal of Applied Mechanics and Engineering

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2021

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Vol. 26, no. 3

84--103

EN

In this paper, a two-dimensional steady flow of a viscous fluid due to a stretching sheet in the presence of a magnetic field is considered. We proposed two new numerical schemes based on the Haar wavelet coupled with a collocation approach and quasi-linearization process for solving the Falkner-Skan equation representing the governing problem. The important derived quantities representing the fluid velocity and wall shear stress for various values of flow parameters Mand βare calculated. The proposed methods enable us to obtain the solutions even for negative β, nonlinear stretching parameter, and smaller values of the magnetic parameter ()M1< which was missing in the earlier findings. Numerical and graphical results obtained show an excellent agreement with the available findings and demonstrate the efficiency and accuracy of the developed schemes. Another significant advantage of the present method is that it does not depends on small parameters and initial presumptions unlike in traditional semi-analytical and numerical methods.

12

Unsteady MHD plane Couette-Poiseuille flow of fourthgrade fluid with thermal radiation, chemical reaction and suction effects

Joseph K. M., Ayankop-Andi E., Mohammed S. U.

International Journal of Applied Mechanics and Engineering

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2021

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Vol. 26, no. 4

77--98

EN

This study investigates the unsteady MHD flow of a fourth-grade fluid in a horizontal parallel plates channel. The upper plate is oscillating and moving while the bottom plate is stationary. Solutions for momentum, energy and concentration equations are obtained by the He-Laplace scheme. This method was also used by Idowu and Sani [12] and there is agreement with our results. The effect of various flow parameters controlling the physical situation is discussed with the aid of graphs. Significant results from this study show that velocity and temperature fields increase with the increase in the thermal radiation parameter, while velocity and concentric fields decrease with an increase in the chemical reaction parameter. Furthermore, velocity, temperature and concentric fields decrease with an increase in the suction parameter. It is also interesting to note that when 4S0=, our results will be in complete agreement with Idowu and Sani [12] results. The results of this work are applicable to industrial processes such as polymer extrusion of dye, draining of plastic films etc.

13

Periodic flow of a second grade fluid due to the disks executing non-torsional oscillations in an orthogonal rheometer under the influence of a magnetic field

Ersoy H. Volkan

International Journal of Applied Mechanics and Engineering

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2021

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Vol. 26, no. 3

62--71

EN

The present paper studies the periodic flow of a second grade fluid generated by non-torsional oscillations of the disks rotating in the eccentric form under the application of a magnetic field. Subsequent to the rotational motion of the disks at a common angular velocity about two vertical axes, they perform oscillations horizontally in a symmetrical manner. The exact analytical solutions are derived for both the velocity field and the tangential force per unit area exerted on one of the disks by the fluid. Special attention is paid to the influence of the applied magnetic field and it is investigated how the magnetic field controls the flow when the frequency of oscillation is less than or equal to or greater than the angular velocity of the disks. It is found that the application of the magnetic field leads to thinner boundary layers developed on the disks and the changes in the values of the shear stress components which represent the tangential force exerted on the disks occur at larger amplitude.

14

Heat and mass transfer effect on an infinite vertical plate in the presence of Hall current and thermal radiation with variable temperature

Manjula L., Muthucumaraswamy R.

International Journal of Applied Mechanics and Engineering

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2021

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Vol. 26, no. 3

131--140

EN

MHD and radiated heat flow on a rotating system of an electrically conducting fluid in the presence of Hall current under the influence of variable temperature is studied analytically. An exact solution of a non-dimensional form of coupled partial differential equations is obtained by the technique of Laplace transform. The effect of temperature, velocity and concentration is analyzed for various parameters like the Hall parameter [...], thermal radiation [...], rotation parameter [...], Hartmann number [...] and results are discussed in detail with the help of graphs. A mixed analysis of a rotating fluid with Hall current and thermal radiation plays a very essential role in the research area such as plasma physics, MHD generator, fluid drift sensor, cosmological and geophysical level, etc.

15

Flow features of thermophoretic MHD viscous fluid flow past a converging channel with heat source and chemical reaction

Kalita B. K., Choudhury R.

International Journal of Applied Mechanics and Engineering

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2021

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Vol. 26, no. 3

72--83

EN

A boundary layer flow of an electrically conducting viscous fluid past a converging channel in the presence of thermophoresis, heat source, chemical reaction, viscous dissipation and simultaneous heat and mass transfer characteristics is studied in the paper. An external magnetic field of uniform strength is applied transversely to the channel. The similarity solution has been used to transform the partial differential equations that represent the problem into a boundary value problem of coupled ordinary differential equations, which in turn are solved numerically using MATLAB’s built in solver bvp4c. Numerical computations are carried out to solve the problem and graphical illustrations are made to get the physical insight of the same. The convergent channel flow problem of an incompressible electrically conducting viscous fluid in the presence of a magnetic field has a wide range of applicability in different areas of engineering, specially in industrial metal casting and control of molten metal flow.

16

Effect of Hall currents on unsteady magnetohydrodynamic two-ionized fluid flow and heat transfer in a channel

Raju T. Linga, Rao V. Gowrisankara

International Journal of Applied Mechanics and Engineering

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2021

|

Vol. 26, no. 2

84--106

EN

An unsteady magnetohydrodynamic (MHD) heat transfer two-fluid flow of ionized gases through a horizontal channel between parallel non-conducting plates, by taking Hall currents into account is studied. The governing partial differential equations that describe the flow and heat transfer under the adopted conditions are solved for the velocity and temperature distributions by a regular perturbation technique. Profiles for the velocity and temperature distributions as well the rates of heat transfer coefficient are presented graphically, and a parametric study is performed. The results reveal that the combined effects of the Hartmann number, Hall parameter, and the ratios of viscosities, heights, electrical and thermal conductivities have a significant impact on an unsteady MHD heat transfer two-ionized fluid flow characteristics.

17

Capture efficiency of magnetically labeled particles traveling through an intracranial aneurysm

Cardona M., Ramírez J., Benavides-Moran A. G.

International Journal of Applied Mechanics and Engineering

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2021

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Vol. 26, no. 1

65--75

EN

Cell manipulation using external magnetic fields has been proposed to accelerate the neck reendothelization of saccular unruptured stented intracranial aneurysms. This work presents a computational fluid dynamics (CFD) model of a Saccular Brain Aneurysm that incorporates a helicoidal stent. An Eulerian-Lagrangian model implemented in ANSYS-Fluent is used to simulate the hemodynamics in the aneurysm. In silico studies have been conducted to describe the incidence of the magnetic field direction, frequency and amplitude on the blood hemodynamics and particle capture efficiency, when an external magnetic field is used to trap magnetically labeled particles traveling through the aneurysm. It is found that the magnetic field direction affects the particle concentration in the target region. Simulation results show that the highest particle capture efficiency is obtained with a 1T magnetic field amplitude in an open bore MRI scanner, when a permanent magnet is used.

18

Effect of thermal radiation on biomagnetic fluid flow and heat transfer over an unsteady stretching sheet

Alam Jahangir Md., Murtaza Ghulam Md., Tzirtzilakis Efstratios E., Ferdows Mohammad

Computer Assisted Methods in Engineering and Science

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2021

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Vol. 28, no. 2

81--104

EN

This study examines the influence of thermal radiation on biomagnetic fluid, namelyblood that passes through a two-dimensional stretching sheet in the presence of magneticdipole. This analysis is conducted to observe the behavior of blood flow for an unsteadycase, which will help in developing new solutions to treat diseases and disorders related tohuman body. Our model is namely biomagnetic fluid dynamics (BFD), which is consistentwith two principles: ferrohydrodynamic (FHD) and magnetohydrodynamic (MHD), whereblood is treated as electrically conductive. It is assumed that the implemented magneticfield is sufficiently strong to saturate the ferrofluid, and the variation of magnetization withtemperature may be approximated with the aid of a function of temperature distinction.The governing partial differential equations (PDEs) converted into ordinary differentialequations (ODEs) using similarity transformation and numerical results are thus obtainedby using the bvp4c function technique in MATLAB software with considering applicableboundary conditions. With the help of graphs, we discuss the impact of various param-eters, namely radiation parameter, unsteady parameter, permeability parameter, suctionparameter, magnetic field parameter, ferromagnetic parameter, Prandtl number, velocityand thermal slip parameter on fluid (blood) flow and heat transfer in the boundary layer.The rate of heat transfer and skin friction coefficient is also computationally obtained forthe requirement of this study. The fluid velocity decreases with increasing values of themagnetic parameter, ferromagnetic interaction parameter, radiation parameter whereastemperature profile increases for the unsteady parameter, Prandtl number, and permeability parameter. From the analysis, it is also observed that the skin friction coefficientdecreases and the rate of heat transfer increases respectively with increasing values ofthe ferromagnetic interaction parameter. The most important part of the present analy-sis is that we neither neglect the magnetization nor electrical conductivity of the bloodthroughout this study. To make the results more feasible, they are compared with thedata previously published in the literature and found to be in good accuracy.

19

Dusty time fractional MHD flow of a Newtonian fluid through a cylindrical tube with a non-Darcian porous medium

Imo-Mani-Singha H., Sengupta Sanjib

Journal of Applied Mathematics and Computational Mechanics

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2020

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Vol. 19, nr 4

101--114

EN

In this paper, time fractional flow of a Newtonian fluid through a uniform cylindrical tube with a non-Darcy porous medium in the presence of dust particles under the application of a uniform magnetic field along the meridian axis is discussed. The implication of time fractional order differential equations in flow problems and some benefits of fractional order differential equations are highlighted. The Laplace Decomposition Method (LDM) is used to obtain an approximate solution to the proposed problem. The impact of fractional order and integer order of the differential equations and also the effects of some important parameters on the flow system are shown in the forms of graphs and a table. The convergence test of the solution is done. It has been observed that the fractional order differential equation reveals more things like the decrease in dust particle velocity due to the increase in magnetic field for fractional order derivatives, whereas, no noticeable change in dust particle velocity due to the change in magnetic field for integer order derivatives are observed. Also, it is observed that an increase in a fractional order derivative decrease the fluid as well as the dust particle velocities. The skin friction at the walls of the tube are also highlighted.

20

Optimization of heat transfer properties of nanofluid flow over a shrinking surface through mathematical modeling

Bhandari A., Pavan Kumar Pannala R. K.

International Journal of Applied Mechanics and Engineering

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2020

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Vol. 25, no. 2

40--56

EN

In the current study, a three dimensional incompressible magnetohydrodynamic (MHD) nanofluid flow over a shrinking surface with associated thermal buoyancy, thermal radiation, and heating absorption effects, as well as viscous dissipation have been investigated. The model has been represented in a set of partial differential equations and is transformed using suitable similarity transformations which are then solved by using the finite element method through COMSOL. The results for velocity and temperature profiles are provided for various values of the shrinking parameter, Biot’s number, heat generation/absorption parameter, thermal Grashof number, nanoparticle volume fraction, permeability parameter, magnetic parameter and radiation parameter.