MHD Heat Transfer Research Articles

Effects of Suction and Lorentz Force on an Unsteady MHD Convective Mass and Heat Transfer Nanofluid Flow upon a Vertical Permeable Sheet

Effects of Suction and Lorentz Force on an Unsteady MHD Convective Mass and Heat Transfer Nanofluid Flow upon a Vertical Permeable Sheet

Chemically Radiative and Slip Effects on MHD Heat and Mass Transfer Flow of Maxwell Nanofluid across an Inclined Surface

In both the laboratory and the manufacturing setting, nanofluids play a crucial role in improving the thermal properties of pure fluids. The heat and mass transmission of an incompressible upper-convected Maxwell fluid along a stretched sheet in the midst of heat radiation, chemical changes, and suction is investigated. The nonlinear slip condition for the Maxwell fluid is put into account herein. The diffusion model for mass and heat transfer introduced by Cattaneo and Christov is incorporated in the modelling process. The partial differential equations that regulate the system are reduced into a more fundamental form via similarity transformations. Mathematica's NDSolve technique is implemented to do a numerical treatment of the dimensionless equations once they have been translated. The upsides of this strategy lie in its ability to automatically track errors and select the best algorithm. Assessments are taken of velocity, temperature, concentration, skin friction, Nusselt number, and Sherwood number, among others. Graphs are used to quickly illustrate and clarify how various material qualities affect the flow of mass and heat transmission. Thermal relaxation and chemical reaction parameters minimize temperature and concentration fields. It is observed that greater Maxwell parameters implies a rise in the intensity of skin friction, whereas a spike in the slip parameter generates a decrease. Nusselt and Sherwood numbers diminish with Maxwell parameter.

Radiation and Nanoparticles Shape Effect on Aligned MHD Jeffrey Hybrid Nanofluids Flow and Heat Transfer over a Stretching Inclined Plate

The study through a stretching medium is a topic in the field of fluid dynamics and heat transfer. It involves investigating the behaviour of fluid flow and heat transfer phenomena in situations where a medium, such as a solid surface, is continuously stretched or deformed. Jeffrey fluid are found in the applications in various fields, including engineering, materials science, and biomedical engineering. Water was combined with copper (Cu) and aluminium oxide (Al2O3) is used in this study by considering the influence of nanoparticles shape which are spherical, brick, cylindrical, platelet and blade. The Keller Box method is used to solve numerically the Jeffrey hybrid nanofluid's governing nonlinear partial differential equations (PDEs) to nonlinear ordinary differential equations (ODEs) using similarity transformation. The results for both the velocity and temperature profiles of Jeffrey hybrid nanofluids (Deborah number, β) as well as the skin friction and Nusselt number are presented graphically and in tabulated form. The result shows that the momentum boundary layer thickness is decrease for any increment of the value alignment angle of the magnetic field parameter, the interaction of the magnetic field parameter, alignment angle of the incline plate, the mixed convection parameter, the radiation parameter, and the nanoparticles shape except the value of the volume fraction of the nanoparticles for the increasing value of Deborah number (β). The skin friction is increases as any increment value of an alignment angle of magnetic field, interaction of magnetic parameter, radiation parameter and volume fraction of nanoparticles increase, while the Nusselt number is decrease for the value of radiation parameter. It also observed that the factor of nanoparticles shape result is significant with the Jeffrey hybrid nanofluids which is the nanoparticles shape with the highest skin friction coefficient and Nusselt number is blades shape.

Chemically reactive MHD convective flow and heat transfer performance of ternary hybrid nanofluid past a curved stretching sheet

One of the topmost challenges of today’s industry age is to find an efficient heat transfer fluid because heat transfer rate in common fluids is unable to provide an efficient heating and cooling process in the industries. Ternary hybrid nanofluids are considered as next generation heat transfer fluids, which are prepared by suspension of three different type of nanoparticles in the base fluids. This novel class of nanofluids, due to its unique and dynamic thermophysical properties, has diverse applications in numerous arenas of nanotechnology and heat transfer appliances. This research article examines an electrically conducting and magnetically influenced 2D flow of modified hybrid nanofluid past a curved stretching sheet. The considered trihybrid nanofluid contains nanometer sized particles of three different materials (CuO, Al2O3, TiO2) suspended in the water. The preliminary assumptions in this numerical investigation include the exponential heating, Brownian motion, chemical factor, and thermophoresis effects. At boundary, convective mass and heat flux constraints are employed. This pragmatic investigation with the aforementioned presumption is conducted for the first time to evaluate heat and mass transference properties of ternary nanofluid past a curved stretchable surface. The problem is mathematically modelled by using the fundamental momentum and energy equations and modified to cater the solid additives concentration in the base fluid. The modelled Partial Differential Equations (PDEs) are subsequently transformed into Ordinary Differential Equations (ODEs) by employing suitable similarity transformation and subsequently solved by the MATLAB software bvp4c to demonstrate role of important controlling parameters in tabular and graphical form. The research concludes that the enhancement of curvature factor enhances the velocity profile while the impact is opposite for magnetic factor. The most important and an interesting aspect of this innovative study is that the rate of heat transfer increases for all embedding parameters (ie M,K,Nb,Nt,Ec,Δt,β,BiT,BiCandQe), which is the basic purpose of using nanofluids for their promising use in nanotechnology. The study reveals that frictional force at the stretching surface decreases by reducing curvature of surface. However, converse trend is observed for increasing magnetic factor. Moreover, said impact of curvature is more prominent for ternary hybrid nanofluid whereas M has greater impact for unitary nanofluid. The greater heat source factor, activation energy, concentration and thermal Biot numbers, temperature difference and thermophoresis factors increase the concentration boundary layer while decreasing trend is observed for Brownian motion, Schmidt number and chemical reaction factor. The Nusselt number increases for higher values of thermal Biot number, thermophoresis parameter and the heat source factor.

Exploration of heat and mass transfer on 3-D radiative MHD Casson fluid flow over a stretching permeable sheet with chemical reaction

The goal of this study is to determine the effect of chemical reaction, radiation, and Prandtl number on 3-D MHD Heat transfer Casson fluid flow through a linearly porous stretched surface. When studying the effects of thermal radiation, the Roseland approximation is utilized since it factors the radiation impact into the energy equation. Due to its many commercial uses and significant influence on a wide range of production processes, heat transfer past a stretched sheet has garnered interest recently. They include power plants, heat exchangers, MHD generators, aerodynamics, plastic sheet extrusion, condensation, and metal spinning. Using similarity variables, the governing equations & allied boundary conditions are simplified to a dimensionless form, and then the problem is solved using the Runge-Kutta-Fehlberg strategy. The reliability and precision of this Runge-Kutta-Fehlberg strategy is shown graphically for a range of relevant parameters and conditions. A comparison of our numerical findings with data that had been formerly published reveals that both sets of data are quite compatible with one another. The results of the current research contribute to the regulation of heat transfer rates and fluid velocities in various manufacturing processes and industrial applications, hence facilitating the production of required quality in the final product.

The Upshot of Nonlinear Thermal Emission on a Conducting Jeffrey Nanofluid Flow over a Stretching Sheet: A Lie Group Approach

The upshot of nonlinear thermal radiation of steady state MHD heat transfer of Jeffrey nanofluid together with prescribed boundary conditions of interest was studied. Essential fluid properties, dimensionless switch parameters with the assistance of the Lie group method were used to transform the convenient partial differential equations that describe the present model into a system of ordinary differential equations. The generalized flow of the present model incorporates Jeffrey parameters and nonlinear thermal radiation. The Mathematical model is first renovated into ordinary differential equations by Lie symmetry group alteration. The renovated equations were solved numerically using a bvp4c MATLAB solver. The Jeffrey parameter serves as a stabilizer on the velocity of the fluid while thermal radiation parameter and heat source-sink parameter improves the flow temperature. Lewis number, chemical reaction parameter diminished the mass transfer flow. Equally skin friction, Sherwood number and Nusselt number were expanded.

Influence of Hall Current and Chemical Reaction on MHD Unsteady Mass and Heat Transfer Flow Under Rotation

Influence of Hall Current and Chemical Reaction on MHD Unsteady Mass and Heat Transfer Flow Under Rotation

The stability of the MHD flow over a shrinking cylinder with surface heat flux and volumetric thermal power

In this analysis, the stability of MHD stagnation point flow and heat transfer of an electrically conducting viscous incompressible fluid on a horizontally stretching/shrinking permeable cylinder with volumetric heat source are investigated. The cylindrical surface is subjected to a cross flow and a heat flux. This analysis finds applications in the areas of polymeric processing unit due to stretching/shrinking of surface and biofluid flows with therapeutic effects through the arteries, vein and digestive system that have a tube-like structure. Other aspects of the analysis are: magnetic field intensity whose strength can be remotely controlled and embodied generating/absorbing thermal power. The solution of the boundary value problems (BVP) is carried out with MATLAB’s inbuilt solver bvp4c. The most significant findings are recorded as: an increase in magnetic field strength increases the skin friction at the solid surface which is consistent with progressive thinning of boundary layer. This striking result is of interest in industrial applications because it is easy to regulate the magnetic field strength by electromagnetic devices such as controlling the voltage in the electric circuit. There is a point of neutrality of thermal energy distribution during the high fluctuation of temperature irrespective of the presence of heat generation or absorption. This can be attributed to the dominating effect of stretching/shrinking of the surface. The first solution provides stability of the flow with an increase in velocity in the presence of heat sink that is commensurate with the strength.

MHD Couette flow and heat transfer in a rotating channel in presence of viscous dissipation and heat source/sink

The fully developed steady flow of an electrically conducting as well as heat-generating/absorbing fluid, in a horizontal rotating channel in the presence of viscous dissipation, has been studied. Further, the flow is subjected to shearing impact due to the motion of the upper plate. The effects of various parameters characterizing the translating and rotating flow and heat transfer phenomena, based on analytical solutions, are depicted with the help of graphs and tables. The solution of the boundary value problem has been carried out analytically and computations thereof with MATLAB code. The outcomes of the present study find applications in the motion of the rotor blade and turbine. The important findings are: the moderate speed of rotation gives rise to inconsistency in heat transfer, a transition state between low and moderately high speed, hence speed of the channel is to be taken care of for smooth and consistent heat transfer; the effect of entire values of Eckert number persists on the temperature distribution; the higher magnetic field intensity gives rise to convex type of temperature field (rise in temperature) resulting thicker thermal boundary layer; whereas the reverse is the case in the presence of sink. Most importantly, the inconsistency of heat transfer at the bounding surface is due to the interaction of electromagnetic force with the rotation of the channel.

Comparison of Adomian Decomposition Method with Differential Transformation Method for Unsteady MHD Flow and Heat Transfer Over a Stretching/Shrinking Permeable Sheet with Ohmic Heating

In this paper, two semi-analytical techniques were implemented to solve a two-dimensional unsteady MHD fluid flow and heat transfer through a stretching/shrinking permeable sheet with ohmic heating and viscous dissipation. The governing flow equations in PDE form were reduced to ordinary differential equations using appropriate similarity transformation. We obtained approximate expressions for the velocity and temperature profiles. Comparative results obtained employing Adomian decomposition method and differential transformation method were benchmarked against a numerical solution using Keller box scheme. Our findings revealed that the approximate analytical solution obtained using DTM is more dependable with fast convergence, highly accurate with minimal calculations and computationally convenient. However, the requirement of Adomian polynomials to tackle the nonlinear terms in ADM makes its execution sometimes cumbersome and difficult.

Correction: Alshehri et al. Unsteady Convective MHD Flow and Heat Transfer of a Viscous Nanofluid across a Porous Stretching/Shrinking Surface: Existence of Multiple Solutions. Crystals 2021, 11, 1359

We ought to correct the misprinted terms in our published paper ‘Unsteady Convective MHD Flow and Heat Transfer of a Viscous Nanofluid across a Porous Stretching/Shrinking Surface: Existence of Multiple Solutions’ [Crystals2021, 11, 1359] [...]

Numerical computation on MHD natural convective ternary nanofluid flow and heat transfer in a porous square cavity: Marker-and-cell technique

PurposeThe analysis of fluid flow and thermal transport performance inside the cavity has found numerous applications in various engineering fields, such as nuclear reactors and solar collectors. Nowadays, researchers are concentrating on improving heat transfer by using ternary nanofluids. With this motivation, the present study analyzes the natural convective flow and heat transfer efficiency of ternary nanofluids in different types of porous square cavities.Design/methodology/approachThe cavity inclination angle is fixed ω = 0 in case (I) and in case (II). The traditional fluid is water, and is treated as a working fluid. Ternary nanofluid's thermophysical properties are considered, according to the Tiwari–Das model. The marker-and-cell numerical scheme is adopted to solve the transformed dimensionless mathematical model with associated initial–boundary conditions.FindingsThe average heat transfer rate is computed for four combinations of ternary nanofluids: and under the influence of various physical factors such as volume fraction of nanoparticles, inclined magnetic field, cavity inclination angle, porous medium, internal heat generation/absorption and thermal radiation. The transport phenomena within the square cavity are graphically displayed via streamlines, isotherms, local and average Nusselt number profiles with adequate physical interpretations.Practical implicationsThe purpose of this study is to determine whether the ternary nanofluids may be used to achieve the high thermal transmission in nuclear power systems, generators and electronic device applications.Social implicationsThe current analysis is useful to improve the thermal features of nuclear reactors, solar collectors, energy storage and hybrid fuel cells.Originality/valueTo the best of the authors’ knowledge, no research has been carried out related to the magneto-hydrodynamic natural convective ternary nanofluid flow and heat transmission filled in porous square cavities with an inclined cavity angle. The computational outcomes revealed that the average heat transfer depends not only on the nanoparticle’s volume concentration but also on the existence of heat source and sink.

Significance of radiation and chemical reaction on MHD heat transfer nanofluid flow over a nonlinearly porous stretching sheet with nonuniform heat source

This article discusses the thermal radiation significance on the 2-D laminar MHD boundary layer flow of a nanofluid, as well as the heat transfer associated with the viscous flow across a nonlinear stretching surface. The flow is produced by a nonlinearly enlarging sheet with varying temperatures in the existence of suction, radiation, and viscous dissipation. By applying suitable similarity conversions, the resultant governed PDEs are transformed to a set of nonlinear ODE’s, and then, they are solved by applying the Keller–Box approach numerically. The impact of several flow pertinent factors on heat, species concentration, and velocity fields are exposed graphically and numerically. Numerical calculations for friction factor, mass, and heat transmission rates are discussed in table form. Prior results were examined under constraining circumstances and found to be adequate. It is discovered that when the velocity slip factor is enhanced, the fluid velocity distribution declines whereas the heat and concentration gradients increase. The principal results indicate that the porosity parameter effectively decreases the velocity distribution.

A Parametric Simulation of MHD Flow and Heat Transfer of Blood-Fe3O4 Over an Exponentially Stretching Cylinder

A Parametric Simulation of MHD Flow and Heat Transfer of Blood-Fe3O4 Over an Exponentially Stretching Cylinder

Heat transfer enhancement in free convection flow of MHD second grade fluid with carbon nanotubes (CNTS) over a vertically static plate

Nanofluids are said to have high potential applicability as an enhanced thermophysical heat transfer fluid and are also related to CMC (carboxymethyl cellulose) due to their increased thermal conductivities. The intention of this research is to investigate and analyze the free convection flow of a second grade MHD heat transfer of CNTs on a vertically static plate with a constant wall temperature. The two types of CNTs are immersed in CMC, named multiple wall carbon nanotubes (MWCNTs) and single-wall carbon nanotubes (SWC-NTs). Nanofluids have been determined to offer a great potential application as an improved thermophysical heat transfer fluid, also due to their higher thermal conductivities. The problem is formulated as PDEs with initial and boundary conditions that are transformed into dimensionless structures by using unique non-dimensional variables. The general solution to the problem is achieved by utilizing the Laplace Transformation approach and obtaining the exact solutions for velocity, temperature, and shear stress. We compared the solutions of SWCNTs and MWCNTs regarding parameters such as Grashof number, relaxation time, Prandtl number, and volume fraction of nanoparticles. The results are significantly influenced by the differences in SWCNTs andMWCNTs.

MHD Flow and Heat Transfer of Water-Based Nanofluid Passing a Permeable Exponentially Shrinking Sheet with Thermal Radiation

The key objective of the present study is to elaborate the concept of boundary layer flow and heat transfer of magnetohydrodynamics namely Cu-water nanofluid flow towards an exponentially shrinking sheet with aid of mathematical modeling and computation. The present mathematical model is investigated under the influence of thermal radiation and suction. Using exponential form of similarity variables, the system of partial differential equations (PDEs) are converted in to a set of ordinary differential equations (ODEs). The resulting nonlinear ODEs are computationally solved by using a two-point boundary value problem numerical technique, which constitutes with common finite difference method. The influence of physical parameters such as magnetic field parameter, Eckert number, suction parameter, radiation parameter are described in details with the help of graphical demonstration of velocity and temperature distributions, coefficient of skin fiction and rate of heat transfer. Computational results reveal that after suspension of nanoparticles into base fluid as water fluid temperature raised significantly compare to that of pure fluid. It is also observed that for rising values of magnetic field parameter, thermal radiation, particles volume fraction fluid temperature distribution significantly improved; whereas opposite phenomena is true for suction parameter and Prandtl number. The rate of heat transfer accelerated with Eckert number, Prandtl number, while coefficient of skin friction boost with thermal radiation parameter. For verifying purposes, a comparison has been shown between present results and the computational results of previous studies and found a very close agreement.

Mathematical Modeling on Magnetohydrodynamics Upper Convected Maxwell Fluid Flow Past a Flat Plate Using Spectral Relaxation Approach

The focus of this treatise is on the scrutiny of MHD heat and mass transfer motion of upper convection Maxwell (UCM) fluid in a thermally radiated flat plate. The models of the flow equations were considered when there is a temperature difference: the Cattaneo-Christov model and the Soret-Dufour mechanisms. A magnetic field of firmness was inflicted in opposition to the flow. The flow inspection is controlled by partial differential equations (PDEs). Suitable similarity variables were utilised on the PDEs to obtain a set of nonlinear ordinary differential equations (ODEs). The simplified set of ODEs shall be answered by exploiting the spectral relaxation method (SRM). The SRM is a numerical technique that solves differential equations by utilising the repetition of a sequence of operations that is iterated iteratively by first decoupling the coupled systems of equations. The magnetism was found to decline the velocity and hydrodynamic boundary layer due to the Lorentz force. The Deborah number was found to enhance the velocity contour. The Eckert number was discovered to improve the temperature profile due to the production of heat energy within the boundary layer. An increase in Prandtl number was found to enhance the hydrodynamic and thermal boundary layer thickness. The local skin friction and Nusselt number were found to be elevated by the increase in the Dufour parameter.

A study under the impact of Soret and Dufour effects on MHD stagnation point flow and heat transfer towards a stretching sheet

This paper signifies the consequence of the thermal diffusion (Soret) and diffusion-Thermo (Dufour) effect on MHD stagnation point flow and transportation of thermal energy near a stretching plate. However, the inclusion of thermal radiation, heat generation/absorption, and chemical reaction enriches the profiles significantly. By using similarity transformation, the set of leading equations is altered into a set of dimensionless ordinary differential equations. After that, the aim is to convert boundary layer equations into dimensionless ones so that the set of converting equations is computed by using bvp4c solver on MATLAB software. The governing nonlinear equations were resolved with Runge–Kutta fourth-order technique numerically. The significance of radiation, magnetic field, suction, Schmidt number, velocity ratio parameter, heat absorption coefficient, permeability, thermo-diffusion number, diffusion-thermo number on momentum gradient, energy gradient and concentration gradient distribution is analyzed. The parameters, diffusion-thermo number Du and thermo-diffusion number Sr have opposite behaviors on both temperature and concentration fields. Here, also, it is observed that the heat sink parameter has a noticeable influence on the fluid temperature distribution profile.

Homotopy Perturbation Method for MHD Heat and Mass Transfer Flow of Convective Fluid through a Vertical Porous Plate in the Presence of Chemical Reaction and Inclined Magnetic Field

The present work is devoted to study a viscous, incompressible, and electrically conducting fluid on an MHD fluid flowing past a semi-infinite porous plate in the presence of chemical reaction and inclined magnetic parameter. The governing equations are expressed in non-dimensional form and the resulting nonlinear equations are solved employing the Homotopy perturbation method for the nondimensional velocity, temperature, and concentration profiles. The effects of various controlling parameters such as Casson parameter, Hartmann number, inclined magnetic parameter, porosity parameter, Grashof number, angle of inclination, Prandtl number, Eckert number, radiation parameter, Schmidt number and thermal radiation parameters are presented graphically and discussed in detail. It was found that, velocity profile is enhanced in the presence of Casson, magnetic field and inclined angle parameters whereas it declined with positive increase in the porosity, Grashof and inclined angle numbers. Similarly, increase in Prandtl, Eckert, radiation and inclined angle numbers lead to increase in the temperature distribution of the fluid, while it deceased as the magnetic field parameter increased. The effect of increased thermal radiation parameter is proportional to the concentration profile, whereas it declines for increase in values of Schmidt number.

Homotopy Perturbation Method for MHD Heat and Mass Transfer Flow of Convective Fluid through a Vertical Porous Plate in the Presence of Chemical Reaction and Inclined Magnetic Field

The present work is devoted to study a viscous, incompressible, and electrically conducting fluid on an MHD fluid flowing past a semi-infinite porous plate in the presence of chemical reaction and inclined magnetic parameter. The governing equations are expressed in non-dimensional form and the resulting nonlinear equations are solved employing the Homotopy perturbation method for the nondimensional velocity, temperature, and concentration profiles. The effects of various controlling parameters such as Casson parameter, Hartmann number, inclined magnetic parameter, porosity parameter, Grashof number, angle of inclination, Prandtl number, Eckert number, radiation parameter, Schmidt number and thermal radiation parameters are presented graphically and discussed in detail. It was found that, velocity profile is enhanced in the presence of Casson, magnetic field and inclined angle parameters whereas it declined with positive increase in the porosity, Grashof and inclined angle numbers. Similarly, increase in Prandtl, Eckert, radiation and inclined angle numbers lead to increase in the temperature distribution of the fluid, while it deceased as the magnetic field parameter increased. The effect of increased thermal radiation parameter is proportional to the concentration profile, whereas it declines for increase in values of Schmidt number.