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1

Unsteady magnetohydrodynamic free convection and heat transfer flow of Al2O3‒Cu/water nanofluid over a non-linear stretching sheet in a porous medium

Mathews Joel, Hymavathi Talla

Archives of Thermodynamics

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2024

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Vol. 45, no 1

165--173

EN

This article investigates the impact of time-dependent magnetohydrodynamics free convection flow of a nanofluid over a non-linear stretching sheet immersed in a porous medium. The combination of water as a base fluid and two different types of nanoparticles, namely aluminum oxide (Al2O3) and copper (Cu) is taken into account. The impacts of thermal radiation, viscous dissipation and heat source/sink are examined. The governing coupled non-linear partial differential equations are reduced to ordinary differential equations using suitable similarity transformations. The solutions of the principal equations are computed in closed form by applying the MATLAB bvp4c method. The velocity and temperature profiles, as well as the skin friction coefficient and Nusselt number, are discussed through graphs and tables for various flow parameters. The current simulations are suitable for the thermal flow processing of magnetic nanomaterials in the chemical engineering and metallurgy industries. From the results, it is noticed that the results of copper nanofluid have a better impact than those of aluminium nanofluid.

2

Soret and Dufour effects on an unsteady MHD flow about a permeable rotating vertical cone with variable fluid properties

Jamir Temjennaro, Konwar Hemanta

Archives of Thermodynamics

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2024

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Vol. 45, no 1

75--86

EN

The objective of the present work is to examine the characteristics of unsteady incompressible magnetohydrodynamic fluid flow around a permeable rotating vertical cone. The effects of thermal radiation, viscous dissipation, and the Soret and Dufour effects are investigated in the analysis of heat and mass transfer. The viscosity of the fluid is considered inversely proportional to the temperature, and the thermal conductivity of the fluid is considered directly proportional to the temperature. The governing equations are converted into ordinary differential equations using suitable similarity transformations, which are then solved numerically using bvp4c from MATLAB. Results obtained in this study are in excellent correlation with previously conducted studies. The results demonstrate that the Dufour and Soret effects subsequently reduce the heat transit rate (by 3.3%) and mass transit rate (by 1.2%) of the system. It is also detected that fluids with higher viscosity tend to increase tangential skin friction (+8.9%) and azimuthal skin friction (+8.3%). The heat transit rate of the system is found to be more efficient for fluids with higher viscosity and lower thermal conductivity and Eckert numbers. Furthermore, the thickness of the momentum, thermal, and concentration boundary layers significantly reduces while the heat and mass transit rates (+17.8% and +18.3%, respectively) of the system become more efficient for greater values of the unsteadiness parameter.

3

Palani G., Arutchelvi A.

International Journal of Applied Mechanics and Engineering

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2023

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Vol. 28, no. 1

71--83

EN

An analysis has been carried out to study the two-dimensional free convective boundary layer MHD nanofluid flow past an inclined plate with heat generation, chemical reaction and radiation effects under convective boundary conditions. The partial differential equations describing the flow are coupled nonlinear. They have been reduced to nonlinear ordinary differential equations by utilizing a similarity transformation, which is then solved numerically with the aid of the Runge-Kutta-based shooting technique. Graphs depict the influence of different controlling factors on the velocity, temperature, and concentration profiles. Numerical findings for skin friction, Nusselt number and Sherwood number are reviewed for distinct physical parameter values. In a limited sense, there is a good correlation between the current study's results and those of the earlier published work.

4

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.

5

Effects of viscous dissipative MHD fluid flow past a moving vertical plate with rotating system embedded in porous medium

Kumari D. Santhi, Sajja Venkata Subrahmanyam, Kishore P. M.

International Journal of Applied Mechanics and Engineering

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2023

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Vol. 28, no. 3

112--126

EN

An incompressible unsteady free convective viscous MHD rotating flow past a moving plate embedded in a porous medium is considered with the influence of viscous dissipation, heat source effects. It is assumed that the flow rotates with angular velocity which is normal to the plate and also that a transverse magnetic field is applied along the normal to the plate. Appropriate dimensionless quantities are applied to change the governing equations into dimensionless form. Then the equations are solved numerically using the Galerkin finite element method. Some important characteristics of the fluid are studied. The results are in good agreement with the available literature.

6

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.

7

Radiation and magnetohydrodynamic effects on convective nanofluid past an inclined plate in the presence of a chemical reaction

Palani G., Arutchelvi A.

International Journal of Applied Mechanics and Engineering

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2022

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Vol. 27, no. 3

115--126

EN

This computational work explores the heat and mass transfer of copper water nanofluid flowing along an inclined plate with varying surface temperature and concentration in the presence of a magnetic field and radiation through a permeable medium. The dimensionless governing equations are solved numerically using an efficient finite-difference technique, which is fast convergent and unconditionally stable. The findings are reviewed and illustrated through graphs for pertinent parameters.

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

Heat transfer in oscillating flow through porous medium with dissipative heat

Guria M.

International Journal of Applied Mechanics and Engineering

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2022

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Vol. 27, no. 2

77--86

EN

In this paper, heat transfer in flow between two horizontal parallel porous plates through a porous medium when the upper plate oscillates in its own plane has been analyzed taking into account the effect of viscous dissipation. An increment in the Prandtl number or Reynolds number results in an increment of the temperature profile. With an increase in viscous dissipative heat the temperature distribution decreases.

10

Heat transfer effects on free convection of viscous dissipative fluid flow over an inclined plate with thermal radiation in the presence of induced magnetic field

Kumar P. Pramod, Malga Bala Siddulu, Appidi Lakshmi, Matta Sweta

International Journal of Applied Mechanics and Engineering

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2021

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Vol. 26, no. 1

122--134

EN

The principal objective of the present paper is to know the reaction of thermal radiation and the effects of magnetic fields on a viscous dissipative free convection fluid flow past an inclined infinite plate in the presence of an induced magnetic field. The Galerkin finite element technique is applied to solve the nonlinear coupled partial differential equations and effects of thermal radiation and other physical and flow parameters on velocity, induced magnetic field, along with temperature profiles are explained through graphs. It is noticed that as the thermal radiation increases velocity and temperature profiles decrease and the induced magnetic field profiles increases.

11

Radiative MHD Walter’s liquid-B flow past a semi-infinite vertical plate in the presence of viscous dissipation with a heat source

Damala Chenna Kesavaiah, Bhumarapu Venkateswarlu, Makinde Oluwole Daniel

Engineering Transactions

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2021

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Vol. 69, iss. 4

373--401

EN

The free convective magnetohydrodynamics (MHD) flow of a non-Newtonian fluid due to a semi-infinite vertical plate under the influence of radiation and viscous dissipation is investigated. The system of partial differential equations is derived and solved for the solutions of velocity and temperature profiles along with the Nusselt number and skin friction by using the perturbation technique. The related important dimensionless parameters of Eckert, Grashof, and Prandtl numbers, magnetic field, radiation and heat source are discussed and shown in graphs. Also, the Nusselt number and skin friction at the plate are obtained and presented in the tabular forms. Finally, the corresponding result of Newtonian fluid is obtained by setting viscoelastic parameter k1 = 0. It is worth mentioning that the obtained results coincide with the previously published results.

12

Mixed convection on MHD flow with thermal radiation, chemical reaction and viscous dissipation embedded in a porous medium

Zigta B.

International Journal of Applied Mechanics and Engineering

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2020

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Vol. 25, no. 1

219--235

EN

In this paper, a theoretical analysis has been made to study the effect of mixed convection MHD oscillatory Couette flow in a vertical parallel channel walls embedded in a porous medium in the presence of thermal radiation, chemical reaction and viscous dissipation. The channel walls are subjected to a constant suction velocity and free stream velocity is oscillating with time. The channel walls are embedded vertically in a porous medium. A magnetic field of uniform strength is applied normal to the vertical channel walls. The nonlinear and coupled partial differential equations are solved using multi parameter perturbation techniques. The effects of physical parameters, viz., the radiation absorption parameter, Prandtl number, Eckert number, dynamic viscosity, kinematic viscosity, permeability of porous medium, suction velocity, Schmidt number and chemical reaction parameter on flow variables viz., temperature, concentration and velocity profile have been studied. MATLAB code is used to analyze theoretical facts. The important results show that an increment in the radiation absorption parameter and permeability of porous medium results in an increment of the temperature profile. Moreover, an increment in the Prandtl number, Eckert number and dynamic viscosity results in a decrement of the temperature profile. An increment in suction velocity results in a decrement of the velocity profile. An increment in the Schmidt number, chemical reaction parameter and kinematic viscosity results in a decrement of the concentration profile.

13

A numerical study of dissipative chemically reactive radiative MHD flow past a vertical cone with nonuniform mass flux

Sambath P., Sankar D. S., Viswanathan K. K.

International Journal of Applied Mechanics and Engineering

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2020

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Vol. 25, no. 1

159--176

EN

A computational model is presented to explore the properties of heat source, chemically reacting radiative, viscous dissipative MHD flow of an incompressible viscous fluid past an upright cone under inhomogeneous mass flux. A numerical study has been carried out to explore the mass flux features with the help of Crank-Nicolson finite difference scheme. This investigation reveals the influence of distinct significant parameters and the obtained outputs for the transient momentum, temperature and concentration distribution near the boundary layer is discussed and portrayed graphically for the active parameters such as the Schmidt number Sc, thermal radiation Rd, viscous dissipation parameter […], chemical reaction parameter […], MHD parameter M and heat generation parameter ]…]. The significant effect of parameters on shear stress, heat and mass transfer rates are also illustrated.

14

Navier slip condition on time-dependent radiating Nanofluid with the soret effect

Suneetha Sangapatnam, Subbarayudu Ketineni, Wahidunnisa Lalahamed, Reddy Polu Bala Anki

Engineering Transactions

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2020

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Vol. 68, iss. 2

177--198

EN

This work concentrates on the study of the two-dimensional hydromagnetic flow of nanofluids over an suddenly started nonlinear stretching sheet in the presence of radiation and dissipation. The Soret effect and heat generation are also taken into consideration. The transformed ordinary differential equations (ODEs) are solved numerically via the MATLAB RK4S approach bvp4c solver with the assistance of similarity variables. The effects of various parameters are explored and shown in graphs and tables. It is noted that the concentration increases as the Soret number increases within the boundary layer. An increase in velocity slip decreases the velocity and a reverse effect is observed for temperature. This model has significance in different areas such as polymer chemical and metallurgical industries, and other fields that use the latest technology and thermo-processed materials such as metallic and glass sheets.

15

Thermal radiation, chemical reaction, viscous and joule dissipation effects on MHD flow embedded in a porous medium

Zigta B.

International Journal of Applied Mechanics and Engineering

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2019

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Vol. 24, no. 3

725--737

EN

An analysis is presented to study the effects of thermal radiation, chemical reaction, viscous and Joule dissipation on MHD free convection flow between a pair of infinite vertical Couette channel walls embedded in a porous medium. The fluid flows by a strong transverse magnetic field imposed perpendicularly to the channel wall on the assumption of a small magnetic Reynolds number. The governing non linear partial differentia equations are transformed in to ordinary differential equations and are solved analytically. The effect of various parameters viz., Eckert number, electric conductivity, dynamic viscosity and strength of magnetic field on temperature profile has been discussed and presented graphically.

16

Effects of viscous dissipation and wall conduction on steady mixed convection Couette flow of heat generating / absorbing fluid

Ajibade A. O., Umar A. M.

International Journal of Applied Mechanics and Engineering

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2019

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Vol. 24, no. 4

12--35

EN

This article theoretically investigated mixed convection flow of heat generating/absorbing fluid in the presence of viscous dissipation and wall conduction effects. The flow is considered to be steady in a vertical channel with some boundary thickness. One of the plates is heated while the other is kept at ambient temperature. The governing flow equations were solved analytically using Homotopy Perturbation Method (HPM). The influences of the governing parameters were captured in graphs, tables and a table was constructed for validation of the work. It is worthwhile to stress that, both the velocity and temperature profiles decrease near the heated plate with an increase in boundary thickness (d) while the reverse cases were observed toward the cold plate. The velocity profile increases near the heated plate with increase in mixed convection parameter (Gre) and decreases towards the cold plate. Rate of heat transfer has been observed to decrease with increase in boundary plate thickness (d) while the critical value of (Gre) increases with growing boundary plate thickness. The study therefore established the importance of boundary plate thickness in mixed convection investigation.

17

Effect of viscous dissipation and thermoporesis on the flow over an exponentially stretching sheet

Srinivasacharya D., Jagadeeshwar P.

International Journal of Applied Mechanics and Engineering

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2019

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Vol. 24, no. 2

425--438

EN

This article analyses the influence of viscous dissipation and thermoporesis effects on the viscous fluid flow over a porous sheet stretching exponentially by applying convective boundary condition. The numerical solutions to the governing equations are evaluated using a local similarity and non-similarity approach along with a successive linearisation procedure and Chebyshev collocation method. The influence of the pertinent parameters on the physical quantities are displayed through graphs.

18

Scrutinization of Joule heating and viscous dissipation on MHD flow and melting heat transfer over a stretching sheet

Kumar K. G., Gireesha B. J., Manjunatha S.

International Journal of Applied Mechanics and Engineering

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2018

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Vol. 23, no. 2

429--443

EN

The present paper deals with an analysis of the combined effect of Joule heating and viscous dissipation on an MHD boundary layer flow and melting heat transfer of a micro polar fluid over a stretching surface. Governing equations of the problem are transformed into a set of coupled nonlinear ordinary differential equations by applying proper transformations and then they are solved numerically using the RKF-45 method. The method is verified by a comparison with the established results with limiting solution. The influence of the various interesting parameters on the flow and heat transfer is analyzed in detail through plotted graphs.

19

Effects of heat and mass flux on MHD free convection flow through a porous medium with radiation and first order chemical reaction

Awasthi B.

International Journal of Applied Mechanics and Engineering

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2018

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Vol. 23, no. 4

855--871

EN

The study of a magneto hydrodynamic (MHD) free convection flow of an incompressible viscous fluid flow past a vertical surface is analyzed by taking into account viscous dissipation under the influence of radiation effect and chemical reaction with constant heat and mass fluxes. The governing partial differential equations have been converted into a set of ordinary differential equations using non dimensional quantities. The perturbation technique has been applied to solve the system of partial differential equations. The velocity, temperature and concentration fields have been studied for the effect of the permeability parameter (α), Grashof number for heat transfer (Gr), Grashof number for mass transfer (Gm), Prandtl number (Pr), magnetic parameter (M), chemical reaction parameter (Kr), Schmidt number (Sc), Eckert number (E), radiation parameter (F) etc. The expressions for the skin-friction, rate of heat transfer and rate of mass transfer are also derived. It is observed that when the radiation parameter increases, the velocity increases near the vertical surface. It is also seen that the concentration decreases with an increase in the chemical reaction parameter (Kr).

20

Effect of thermal radiation, chemical reaction and viscous dissipation on MHD flow

Zigta B.

International Journal of Applied Mechanics and Engineering

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2018

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Vol. 23, no. 3

787--801

EN

This study examines the effect of thermal radiation, chemical reaction and viscous dissipation on a magnetohydro- dynamic flow in between a pair of infinite vertical Couette channel walls. The momentum equation accounts the effects of both the thermal and the concentration buoyancy forces of the flow. The energy equation addresses the effects of the thermal radiation and viscous dissipation of the flow. Also, the concentration equation includes the effects of molecular diffusivity and chemical reaction parameters. The gray colored fluid considered in this study is a non-scattering medium and has the property of absorbing and emitting radiation. The Roseland approximation is used to describe the radiative heat flux in the energy equation. The velocity of flow transforms kinetic energy into heat energy. The increment of the velocity due to internal energy results in heating up of the fluid and consequently it causes increment of the thermal buoyancy force. The Eckert number being the ratio of the kinetic energy of the flow to the temperature difference of the channel walls is directly proportional to the thermal energy dissipation. It can be observed that increasing the Eckert number results in increasing velocity. A uniform magnetic field is applied perpendicular to the channel walls. The temperature of the moving wall is high enough due to the presence of thermal radiation. The solution of the governing equations is obtained using regular perturbation techniques. These techniques help to convert partial differential equations to a set of ordinary differential equations in dimensionless form and thus they are solved analytically. The following results are obtained: from the simulation study it is observed that the flow pattern of the fluid is affected due to the influence of the thermal radiation, the chemical reaction and viscous dissipation. The increment in the Hartmann number results in the increment of the Lorentz force but a decrement in velocity of the flow. An increment in the radiative parameter results in a decrement in temperature. An increment in the Prandtl number results in a decrement in thermal diffusivity. An increment in both the chemical reaction parameter and molecular diffusivity results in a decrement in concentration.