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1

Soret and dufour effects on chemically reacting and viscous dissipating nanofluid flowing past a moving porous plate in the presence of a heat source/sink

Aastha Aastha, Chand Khem

Acta Mechanica et Automatica

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2023

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Vol. 17, no. 2

263--271

EN

This study performed a numerical investigation of the Soret and Dufour effects on unsteady free convective chemically reacting nanofluid flowing past a vertically moving porous plate in the presence of viscous dissipation and a heat source/sink. The equations direct-ing the flow are non-dimensionalised, modified to ordinary differential equations and emerging equations are resolved computationally by using the bvp4c function in MATLAB software. The results obtained from this analysis indicate that the resulting velocity of the nanofluid increases with increasing Grashof number, mass Grashof number and porosity parameter. An increase in the Dufour number increases the fluid temperature, whereas the concentration profile declines with the increase in the Schmidt number. It is also observed that the skin fric-tion coefficient, Nusselt number and Sherwood number increase with increasing magnetic field parameter, Eckert number and Schmidt number, respectively. The present study reveals the impact of Soret and Dufour effects on heat and mass transfer rates in chemically re-acting and viscous dissipating nanofluids.

2

Natural convection in a hydrodynamically and thermally anisotropic non-rectangular porous cavity: effect of internal heat generation/absorption

Chandran P., Sacheti N. C., Bhadauria B. S., Singh A. K.

International Journal of Applied Mechanics and Engineering

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2018

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Vol. 23, no. 3

595--609

EN

Laminar natural convection in a trapezoidal porous vertical cavity has been investigated in this work. It is assumed that the porous enclosure is filled up with a permeable material subject to hydrodynamic and thermal anisotropy, the flow being governed by the Darcy law as applicable to a non-isotropic medium. It is further assumed that (i) there is heating at the left vertical wall and cooling at the right wall of the enclosure and (ii) the flow domain is subject to the presence of heat source or heat sink. The partial differential equations governing the resulting free convection have been solved numerically in the non-dimensional forms. There arises a number of parameters relating to buoyancy, internal heating, cavity aspect ratio and inclination of the upper surface to the horizontal. The influence of these parameters has been illustrated and analyzed through contours of streamlines and isotherms. We have also discussed the role of internal heating as well as anisotropy on the heat transfer characteristics.

3

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.

4

Unsteady convection flow of a magnetomicropolar fluid past a vertical porous plate

Jain N. C., Gupta P., Sharma B.

International Journal of Applied Mechanics and Engineering

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2013

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Vol. 18, no. 1

43--53

EN

The paper deals with an unsteady two dimensional laminar slip flow of a viscous incompressible magnetomicropolar fluid past a semi infinite porous plate embedded in a porous medium. The flow is under the influence of a transverse magnetic field and heat source/sink. The free stream velocity follows an exponentially increasing or decreasing small perturbation law. The porous surface absorbs the fluid with time varying suction velocity. Expressions are obtained for velocity and temperature fields, mean angular velocity, skin friction and the Nusselt number.

5

Heat transfer of viscoelastic fluid flow due to nonlinear stretching sheet with internal heat source

Nandeppanavar M. M., Siddalingappa M. N., Jyoti H.

International Journal of Applied Mechanics and Engineering

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2013

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Vol. 18, no. 3

739--760

EN

In the present paper, a viscoelastic boundary layer flow and heat transfer over an exponentially stretching continuous sheet in the presence of a heat source/sink has been examined. Loss of energy due to viscous dissipation of the non-Newtonian fluid has been taken into account in this study. Approximate analytical local similar solutions of the highly non-linear momentum equation are obtained for velocity distribution by transforming the equation into Riccati-type and then solving this sequentially. Accuracy of the zero-order analytical solutions for the stream function and velocity are verified by numerical solutions obtained by employing the Runge-Kutta fourth order method involving shooting. Similarity solutions of the temperature equation for non-isothermal boundary conditions are obtained in the form of confluent hypergeometric functions. The effect of various physical parameters on the local skin-friction coefficient and heat transfer characteristics are discussed in detail. It is seen that the rate of heat transfer from the stretching sheet to the fluid can be controlled by suitably choosing the values of the Prandtl number Pr and local Eckert number E, local viscioelastic parameter k1 and local heat source/ sink parameter β.

6

Free convective heat and mass transfer flow over a non-isothermal stretching sheet with added heat source and thermal diffusion in a saturated porous medium

Pravin V. K., Rajagopal K., Veena P. H., Umesh K. S.

International Journal of Applied Mechanics and Engineering

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2011

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Vol. 16, no 1

177-194

EN

The present paper deals with the study of MHD free convection and mass transfer flow of an incompressible viscous fluid past a continuously moving non-isothermal infinite vertical sheet in non-Darcy porous media in the presence of large suction under the influence of uniform magnetic field considering heat source and thermal diffusion with viscous dissipation, inertia term and stress work. Introducing the usual similarity transformations, the equations of momentum, energy and concentration are made linear. To obtain the solution of the problem, ordinary differential equations are solved analytically. The effects of various physical parameters such as the magnetic parameter, permeability parameter, inertia parameter, suction/blowing parameter on heat transfer characteristics are analysed. One of the important findings of our study is that of increasing the value of the inertia parameter k3 decreases the velocity profile and to increase the temperature profile.

7

Effect of radiation on temperature distribution in three-dimensional Couette flow with heat source/sink

Sharma B. K., Sharma P. K., Chand T.

International Journal of Applied Mechanics and Engineering

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2011

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Vol. 16, no 2

531-542

EN

An analysis of a three-dimensional Couette flow with radiation effect on temperature distribution in the presence of heat source/sink is analysed, when the injection of the fluid at the lower stationary plate is transverse sinusoidal and its corresponding removal by constant suction through the porous plate in uniform motion. Due to this type of injection the flow velocity becomes three-dimensional. The effect of the Prandtl number, injection and source/sink parameters on the rate of heat transfer is examined. The Prandtl number has a much greater effect on the temperature distribution than the injection or source/sink parameters.

8

MHD fluctuating free convective flow with radiation embedded in porous medium having variable permeability and heat source/sink

Sharma B., Agarwal M., Chaudhary R. C.

Journal of Technical Physics

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2006

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Vol. 47, no 1

47-58

EN

The study of free convective two-dimensional unsteady flow with radiation through a porous medium of variable permeability and transverse magnetic field in presence of a heat source/sink, bounded by an infinite vertical porous plate with uniform suction, has been made. The permeability of a porous medium fluctuates with time about a constant mean. Approximate solutions for velocity, temperature and skin friction are obtained and the effects of heat source/sink, radiation, variable permeability, Prandtl number and magnetic field parameter on velocity, temperature and skin friction are shown and discussed with the help of graphs and a table.