MHD Natural Convection Flow Research Articles

MHD Natural Convection Flow of Casson Ferrofluid at Lower Stagnation point on a Horizontal Circular Cylinder

MHD Natural Convection Flow of Casson Ferrofluid at Lower Stagnation point on a Horizontal Circular Cylinder

Effect of Suction/Injection on Unsteady MHD Natural Convection Flow of Heat Mass Transfer in Porous Channel in the Presence of Soret Term

This research paper explores the effect of suction/injection on unsteady MHD natural convection flow of heat mass transfer in porous channel in the presence of Soret term. The governing partial differential equations are converted to non- dimensional forms and solved numerically by using unconditionally stable and convergent implicit finite difference method. A parametric study illustrating the influence of various physical parameters is performed. It is reported that the velocity profile increases as Soret term, Grashof number, Solutal Grashof number and Porous parameters values increase, while Magnetic field parameter decreases the velocity profile. The temperature profile rises by the influence in increasing values of Variable Thermal Conductivity and decreases by increasing values of Prandtl number and Radiation parameters. While concentration profile increase by the increasing values of Soret term and Chemical reaction. The dependence of the skin friction coefficient, rate of heat transfer and mass transfer on these parameter has been discussed.

Laminar boundary layers in three‐dimensional MHD natural convective flow past a semi‐infinite vertical plate with variable sinusoidal suction

AbstractThe primary goal of this study is to investigate how the diffusion‐thermo and thermo‐diffusion affect a three‐dimensional hydromagnetic natural convective flow of a radiating fluid past a uniformly moving isothermal and isosolutal semi‐infinite vertical plate subjected to a sinusoidal suction velocity. The asymptotic series expansion method is adopted to solve the equations governing the flow model and to find the analytical solutions. The effect of variable suction on the flow and transport characteristics is mainly highlighted in the study. Both the diffusion‐thermo and thermo‐diffusion effects improve the fluid velocity.

Predicting heat transfer rate and system entropy based on combining artificial neural network with numerical simulation

PurposeThe purpose of this paper is to present numerical simulations for magnetohydrodynamics natural convection of a nanofluid flow inside a cavity with an H-shaped obstacle based on combining artificial neural network (ANN) with the finite element method (FEM), and predict the heat transfer rate and system entropy.Design/methodology/approachThe enclosure is assumed to be inclined. Changing the inclination angle results in a different obstacle shape, which affects the buoyancy force. Hence, different configurations of the contours of the fluid flow, isotherms and the entropy of the system are obtained. The outer walls of the cavity as well as the central part of the obstacle are kept adiabatic. The left vertical portion of the hindrance is cooled, whereas the right vertical part of the obstacle is a heated wall. Using dimensionless variables allows obtaining a dimensionless version of the governing system of equations that is solved via the consistency FEM. The coupled problem of pressure and velocity is overcome via the Increment Pressure Correction Scheme, which is known for its accuracy and stability for similar simple problems. A numerical computation is performed across a broad range of the governing parameters. A total of 304 data sets were used in the development of an ANN model. That data set was conducted from the numerical simulations. The data set underwent optimization, with 70% sets used for training the model, 15% for validation and another 15% for the testing phase. The training of the network model used the Levenberg–Marquardt training algorithm.FindingsFrom the numerical simulations, it is concluded that the H-shaped obstacle boosts heat transfer rate in comparison with the I-shaped case. Also, raising the value of the inclination angle improves the entropy of the system presented by the Bejen number. Furthermore, strength heat transfer rate is obtained via decreasing the Hartmann number while this decrease decays the values of the Bejen number for both positive and negative amounts of the nonlinear Boussinesq parameter. Slower velocity and a better heat transfer rate characterize nanofluid compared with pure fluid. Leveraging the capabilities of the ANN, the developed model adeptly forecasts the values of both the average Nusselt and Bejen numbers with a high degree of accuracy.Originality/valueA novel fusion of FEM and ANN has been tailored to forecast the heat transfer rate and system entropy of MHD natural convective flow within an inclined cavity containing an H-shaped obstacle, amid various physical influences.

Radiation absorption effect on MHD natural convective flow past an impulsively started infinite vertical plate with chemical reaction and thermal radiation

AbstractThe current work is interested on investigating the impacts of thermal radiation, chemical reaction, and absorption radiation of a hydromagnetic convection‐free mass and heat transfer flow in case of an electrically conducting fluid that passes through a vertical plate moving impulsively. The analytical solutions of the governing momentum, energy, and species concentration equations with the initial and boundary conditions are obtained by the Laplace transformation technique. Graphs for fluid characteristics are used to analyze the impact of changing parametric quantities such as M, N, Sc, Kc, Q, Gr, Gm, and t on the temperature, velocity, concentration, and Sherwood number. We derive the engineering curiosity expressions for the Nusselt number and stress, and at the end, we tabulate and discuss the consequences of new parameters. The magnetic field effect and the chemical reaction are seen to diminish the fluid velocity and concentration, respectively, but in contrast, the absorption radiation effect is seen to accelerate both velocity and temperature. It is closely studied that the Nusselt number and skin friction values for hydrogen consistently exceed those for carbon monoxide.

An Analytical Investigation of MHD Natural Convective Flow of a Polar Fluid in Two Vertical Concentric Cylinders with Hall Current and Heat Source

An Analytical Investigation of MHD Natural Convective Flow of a Polar Fluid in Two Vertical Concentric Cylinders with Hall Current and Heat Source

Computational study of double diffusive MHD natural convection flow of non-Newtonian fluid between concentric cylinders

This study investigated double diffusion natural convection of Casson fluids in an asymmetrical cavity under a constant magnetic field. The intricacies of flow and heat/mass transfer were explored computationally using the finite element method. With applications in fields such as geology, oceanography, metallurgy, and astrophysics, it investigates the impact of key parameters like the Rayleigh number, Casson parameter, buoyancy ratio, Hartmann number, and Darcy number on entropy generation, fluid velocity, and temperature/concentration gradients. The findings illustrate that increasing the Rayleigh number enhances convection and entropy, while a higher Casson parameter leads to reduced mixing due to the fluid's more solid-like behavior. Enhancing the buoyancy ratio improves heat and mass transfer, and a greater Darcy number boosts convection efficiency. Additionally, a higher Hartmann number reduces fluid friction but increases mass diffusion and magnetic disorder, subtly improving thermodynamic efficiency. This research offers valuable insights for optimizing heat transfer and energy efficiency in high-temperature industrial processes, contributing to advancements in sustainability and energy utilization.

Characteristics of MHD Jeffery Fluid Past an Inclined Vertical Porous Plate

This paper is concerned with the study of an unsteady, MHD natural convective boundary layer flow of a viscous, incompressible and electrically conducting, non-Newtonian Jeffery fluid over a semi-infinite vertically inclined permeable moving plate embedded in a porous medium in the presence of thermal radiation, heat absorption and thermal diffusion, heat and mass transfer. . The permeability of the porous medium and the suction velocity are considered to be an exponentially decreasing function of time. The fundamental governing equations for this investigation are solved numerically using the perturbation technique. The results are presented graphically and in tabular form for various controlling parameters. The behavior of different physical parameters is shown graphically. The numerical values of Skin friction, Nusselt number, and Sherwood number are presented in a tabular form. Obtained outcomes are compared with earlier studies in the special case and strong agreement is noted. From graphical representation, it is concluded that velocity and temperature distribution increases with the mixed convection parameter and buoyancy force parameter. An increasing value of magnetic field parameter, slip parameter, and Jeffery parameter tends to reduced velocity and also raising the values of Prandtl number, radiation parameter and heat absorption parameter tends to downfallen temperature profiles. This study may be useful in several industrial applications, for example, polymer production, manufacturing of ceramics or glassware and food processing, and so forth.

MHD Natural Convection Flow of Casson Ferrofluid over a Vertical Truncated Cone

MHD Natural Convection Flow of Casson Ferrofluid over a Vertical Truncated Cone

Numerical analysis of heat and mass transfer of MHD natural convection flow in a cavity with effects of source and sink

The study of fluid flow and heat transport is found in many engineering applications such as boilers, nuclear plants, thermal energy storage, and underground pipelines. This study focuses on investigating the effects of isothermal source and sink on natural convection and entropy generation for Casson fluids using the finite element method. Under these considerations, fins ensure the effectiveness of heat transfer systems and flow patterns. Results describe that a higher Ra value leads to promote heat and mass transfer while Ha has the opposite impact. By increasing Ha value, results to retard convective heat transfer. As the Lewis number increases, so does the entropy due to deformation and the Bejan number. The shape optimization study about fins is performed in detail. The aspect ratio of cold fins is varied from 1.25 to 7, found that length and width are nearly directly related to entropy, mass, and heat transfer rates. The correlation coefficient for mean Nusselt and Sherwood number versus sink width is 0.9942, very close to 1, showing a very close direct relationship. The linear regression coefficients for mean Nusselt, Sherwood number and total entropy versus sink lengths are (0.7484, 2.2343), (0.7706, 2.254) and (2.4927, 5.8662), respectively.

Impacts of chemical reaction, thermal radiation, and heat source/sink on unsteady MHD natural convective flow through an oscillatory infinite vertical plate in porous medium

The main objective of this exploration is to analyze the effects of heat source/sink, chemical reactions, and radiation on the unsteady free convective flow through a porous medium using an infinitely oscillating vertical plate. The Laplace transformation tactics is utilized to solve the governing equations for concentration, energy, and momentum. The simulation results demonstrate that the chemical reaction parameter dwindles both primary and secondary velocities. It has been noted that an upsurge in heat generation (heat source) enhances the temperature field, while a decrease in heat absorption (heat sink) leads to a reduction in the temperature field. Furthermore, the radiation parameter causes a drop in both temperature and velocity patterns. The equation for skin friction is derived and presented graphically, and 3-dimensional surface plots are provided to depict the Nusselt number and Sherwood number. Additionally, graphical illustrations are employed to showcase the influence of various non-dimensional variables on concentration, temperature, and velocity patterns.

MHD natural convection flow in a porous medium-filled corrugated enclosure: Effect of heat sources with different heights

A two-dimensional natural convection flow problem in a porous medium-filled enclosure with electrically conducting fluids and solid heat sources of different heights is numerically investigated in this study. The top boundary is cold, and the vertical side boundaries are insulated, while rectangular-shaped corrugations at the lower boundary are generated by placing heat sources. Three distinctive cases are considered concerning the height of the solid rectangular-shaped heat sources. The nonlinear coupled transport equations are discretized by using a higher-order compact (HOC) finite difference scheme. First, existing numerical and experimental data are used to validate the developed code. Then, the effect of key parameter values, like Hartmann number (25–150), Rayleigh number (103–106), Darcy number (10−5–10−1), and Prandtl number (0.015–10), on the convective flow in the corrugated enclosure is analysed. The influence of the permeability of the porous medium is abundantly seen for a range of significant parameter values with a fixed high Rayleigh-Darcy number. The formation of primary, secondary, tertiary, and quaternary vortices affects the thickness of the thermal boundary layer on both hot and cold surfaces in both symmetric and asymmetric patterns. In addition, possible multiple steady states are observed in the Case 2 at Pr=10.0. The local and average Nusselt numbers remains constant on the bottom cold surfaces of the corrugated enclosure, while significant variations are observed on the upper surfaces of the heat sources. These findings are analysed by conducting stream-function (ψ), isotherms (T), local (Nuh,Nuv), and average (Nū) Nusselt number plots. The intensities of heat transfer rate are also examined by analysing Nusselt numbers as a function of Prandtl, Darcy, Rayleigh and Hartmann numbers. Analysing natural convective heat transfer fluid flow in an enclosure with heat sources is prominent for ample engineering applications such as solar collectors, designing nuclear reactors, chemical energy production systems, building constructions and microelectronic equipment, to name a few.

Effects of Injection/Suction on Unsteady MHD Natural Convective Radiative Flow of Heat Mass Transfer in a Plumb Frequency

This paper explores the effects of injection/suction on MHD unsteady natural convective radiative flow of heat mass transfer in a plumb frequency. The governing partial differential equations are converted to non- dimensional forms and solved numerically by an efficient, implicit, iterative method of Crank Nicolson. Suction/injection is used to control the fluid flow in the channel, and an exothermic chemical reaction of Arrhenius kinetic is considered. A parametric study illustrating the influence of various physical parameters is performed. Numerical results for the velocity, temperature, ad concentration as well as the skin friction factor, surface heat and mass transfer rates have been presented for parametric variations of injection/suction, Grashof number, MHD, Prandtl number and Schmidt number. It is reported that the velocity profile increase as thermal grashof number increases. The temperature profile rises by the influence in increasing values of injection and decreases by increasing values of suction parameter. While concentration profile decreases by the increasing values of chemical reaction in the case of suction and injection. The dependence of the skin friction coefficient, rate of heat transfer and mass transfer on these parameters has been discussed.

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.

Thermal performance of MHD natural convection flow in a concentric semi-circle porous enclosure having corrugated radius

The amplitude and period of the corrugation can significantly affect heat transport in a concentric semi-circular enclosure with corrugated radius. By increasing the surface area of the walls and promoting convective heat transmission between the fluid and the walls, the corrugated walls can improve heat transfer. Such a type of system is utilized in energy storage systems, heat exchangers, chemical reactors, materials processing, and electronic cooling systems. The system's overall efficiency and dependability can be increased by using transverse MHD together with corrugated wall to control fluid flow and improve heat and mass transfer. Heat transfer enclosed in a semi-circular porous cavity with corrugated radius walls is addressed. Inner and out semi-circle are joint through heated corrugated walls and these walls are depending upon the amplitude and period of corrugation. The outer semi-circle is divided into three different portions with an angle of 60o each. The central portion is considered as adiabatic however the left and right part of outer semi-circle is cold. The governing equation are developed through law of conservation of mass, momentum, and energy. An inclined magnetic field is applied to the system that makes an angle αwith x−axis. The dimensionless system of nonlinear partial differential equations (PDE) is tackled through Finite Element Method (FEM) and parametric control analysis is developed. The impact of each parameter, for instance: inclination angle −60o≤α≤60o,Rayleigh number (104≤Ra≤108), the Permeability parameter (10−7≤Da≤10−2), Ha is the Hartmann number, amplitude (A) and period of corrugation (20≤f≤60) is reflected through isotherms and streamlines. The results depict that due to transverse angle of MHD, natural convection process within the cavity tilted either on right or left side based upon angle inclination angle. It is concluded that rate of heat transfer is increased by corrugation by increasing the radius's amplitude and higher Darcy numbers signify greater fluid flow resistance, and lower Darcy numbers signify less resistance. They acquire to the conclusion that the Raleigh number's impact on the isotherms profile can be further modified by the strength and direction of the magnetic field.

Thermal influence of heated fin on MHD natural convection flow of nanofluids inside a wavy square cavity

Thermal influence of heated fin on MHD natural convection flow of nanofluids inside a wavy square cavity

Augmenting the Energy Transport Through Magnetic Ferrofluid Filled Inside the I-Shaped Cavity Under the Influence of Thermal Radiation

The effects of heat generation/absorption and thermal radiation on MHD natural convective flow inside the I-shaped cavity saturated with ferrofluid have been investigated in this study. The Cobalt-kerosene type of ferrofluid has been used with solid volume fractions (Φ = 0∼0.06). The penalty finite element technique with Galerkin weighted method has been used to attain the solution of highly non-linear governing PDE’s. Simulations are carried out in terms of stream lines, heat-lines, isotherms contours and local Nusselt number for wide range of physical flow parameters including thermal radiation (NR = 0∼10), heat generation/absorption (ξ = −5∼5), Hartmann (Ha = 0∼10), Rayleigh (Ra = 103∼106), Prandtl (Pr = 6.83), Eckert (Ec = 10−5) and Magnetic number (Mn = 5 * 102). The obtained results show that increasing the concentration of solid volume friction (Φ) from 0 (pure base fluid) to 0.06 has improved heat transfer by 28% and velocity profiles by 23%. Increasing the Rayleigh number from 103 to 106 has significantly improved the total heat transfer rate along the bottom wall from 1.12 to 8.842. It is also noted that the intensity of circulation cells of streamlines and headlines has decreased with increasing Hartmann number (Ha).

Investigation of MHD natural convective flow of optically thick medium-radiating CNT Casson nanofluid over an infinite flat plate with reference to Caputo fractional derivative: As an application to water purification

In this article, the application of Caputo fractional operators of order α, α∈ (0,1) has been studied. Heat transmission near the surface of a vertical plate in the flow of optically thick radiating Casson nanofluid along with mass diffusion in the presence of heat source/sink and constant magnetic flux is investigated. In the fluid problem, an H2O-based Casson nanofluid with carbon nanotube (CNTs) suspensions is investigated. The non-dimensionalized governing PDEs have been solved analytically via the combination of Fourier-sine and Laplace transform techniques and closed form of solutions are attained for the velocity, temperature, and concentration fields in terms of the Mittag-Leffler function. The physical behavior of the significant parameters has been scrutinized graphically. As a result, it is identified that the concentration, temperature, and velocity curves escalate drastically with the raising values of the fractional quantity α due to the alteration in mass, thermal, and momentum boundary layers with higher values of time t. When t>1, the species level in the fluid along with the fluid temperature and velocity rises with the fractional quantity α and decelerates when 0<t<1. Further analysis reveals that as the magnetic field is strengthened, the flow curves decelerate rapidly. Also, tables have been presented to show the influence of the controlling physical quantities on the friction drag and heat transmission rate.

Radiative effects on unsteady MHD natural convection flow in an inclined wavy porous cavity using hybrid nanofluid containing a square obstacle

The introduction of hybrid nanofluids is a significant notion in several engineering and industrial applications. It is utilized prominently in diverse engineering applications, such as low-pressure drop, wider absorption range, generator cooling, good thermal conductivity, nuclear system cooling, heat exchangers. The present model describes the unsteady MHD free convection flow in an inclined wavy permeable enclosure using hybrid nanofluid (Aluminum oxide/Copper-water) containing a square obstacle with the effects of radiation and heat generation/ absorption. The flow is buoyancy-driven and is subjected to heat radiation (Rd) and an angled magnetic field that is constant (B0). The left wall of the cavity is partially heated and cooled by the wavy-right wall, while the remaining sides are adiabatic and contain a square solid block. A numerical Finite difference technique is utilized to resolve the governing PDEs formulated in stream function, temperature and nanoparticle volume fraction. The acquired results are validated with previous numerical studies. The parameters number in this study are discussed as the inclination angle 0°⩽α⩽π/2, Dimensionless heat source length (0.2 ≤ B ≤ 0.8), porosity of the porous medium 0.1⩽ε⩽0.9 dimensionless location of the left heater (0.3 ≤ D ≤ 0.7), Heat generation -2⩽Q⩽2, nanoparticles volume fraction (0.01 ≤ φ ≤ 0.02), thermal radiation 0⩽Rd⩽10 and the Hartmann number (0 ≤ Ha ≤ 100). The results show that improving the porosity raises the average Nusselt number; however, the rate of increase is greater at higher heat flux locations. The average Nusselt number grows when the nanoparticle volume fraction raises in Rd. The distribution of isothermal lines is slightly reduced for the higher value of the Hartman number. Natural convective hybrid nanofluid flow in a wavy porous square cavity combined with heat source/sink has a vital role in various engineering and industrial processes such as solar collector electric machinery, creation of constructing shelters and attics.

Unsteady MHD natural convection flow past an infinite vertical porous plate with radiation absorption effects

AbstractIn this paper, we have explored the unsteady hydromagnetic free convective flow over an infinite perpendicular porous plate with temperature resource and/or radiation absorption. The prevailing equations are subsequently resolved systematically by utilizing perturbation methodology. The velocity, temperatures as well as concentrations sketches are shown in graphics. The impacts in the flow area for dissimilar leading parameters have been explored. Also, the skin friction, Nusselt quantity along with Sherwood quantity are computed with different parameters and mentioned in the tables. The velocity diminishes with escalating in the chemically reacting parameter as well as improves with an increment in temperature resource parameters. The temperature field reduces with an augment in the Prandtl number, whereas it enlarges with an augment in temperature absorption parameters. The concentrations field is enhanced by an amplifying in chemically reacting variable, whereas it lessens with an amplifying Schmidt number.