MHD Effects Research Articles

New trends of fractional modeling and heat and mass transfer investigation of (SWCNTs and MWCNTs)-CMC based nanofluids flow over inclined plate with generalized boundary conditions

In this paper, we have considered unsteady MHD viscous fluid flow of Carboxyl methyl cellulose (CMC) as based fluid and Carbon nanotubes CNTs (SWCNTs, MWCNTs) nanoparticles passing through an inclined plate of infinite length. Furthermore, the effects of heat source, chemical reaction, porosity and MHD are considered. Fractional model is developed by Caputo time fractional derivatives though recent trends of fractional modeling. The semi exact solutions are obtained for the governing equations in dimensionless form by Laplace transform method. Influence of fractional and other flow parameters on temperature, concentration and velocity fields are graphically illustrated. The Nusselt number, Sherwood number and skin friction are computed for fixed values of flow parameters and presented in tabular form. As a result, for larger values of fractional parameters temperature, concentration and velocity fields can be enhanced. A comparison has been drawn between SWCTs-CMC and MWCTs-CMC based nanofluids and found that MWCTs based nanofluids are more efficient in heat transfer than SWCTs-CMC based nanofluids. Further, in the absence of nanoparticles the obtained results are reduced to recently published results and this fact have been proved graphically and they are in good agreement.

On the stagnation point flow of nanomaterial with base viscoelastic micropolar fluid over a stretching surface

Two dimensional Maxwell micropolar fluid flow over a stretching surface is considered in the current analysis. We have highlighted the impacts of viscoelasticity to analyze the flow behavior under the assumptions of nanomaterial over a stretching surface. We also considered the effects of MHD and slip effects for both suction/injection cases. The micropolar non Newtonian nanofluid flow has been presumed in the steady case. Using the boundary layer assumptions and the micro-interia theory for Maxwell nano fluid we have presented the two dimensional momentum equations. This system has become dimensionless when we applied the similarity transformations. The dimensionless system has solved to find the effects of flow behavior through numerical scheme bvp4c method. The physical dimensionless parameters which involved in the flow assumptions are highlighted through graphs and tables. We discussed the skin friction and heat transfer rate as the surface. Some meaningful results are developed which may be helpful in the field of engineering and science. We have been noted that with the increase of δm,σsandρs/ρf, the nondimensional velocity f′(η) increases while temperature θ(η) gives the decline behavior for higher values of δm,σsandρs/ρf. Surprisingly, the skin friction and heat transfer rate at the surface are both increases for enhancing ϕ.

Magnetohydrodynamics Mixed Convection Effects on the open enclosure in a horizontal channel Heated Partially from the Bottom

This paper presents a numerical simulation of MHD effects on laminar fluid flow throws a two-dimensional channel with an open cavity heated partially from the bottom with a constant length for the heated wall. A constant speed fluid flow (air) inters the horizontal channel at constant cold temperature and all the walls assumed to be insulated accept the heated wall at the bottom of the open cavity. In this study, COMSOL Multiphysics® Modelling Software (5.5) have been selected to solve the governing equations The results are carried out with a verity range of Richardson number and Hartmann number, while the Reynolds number and Prandtl number are kept constants (Re= 100, and Pr=0.707). The result shows that the heat transfer increases with increasing of the Richardson number, while it decreases with the increase of the magnetic field effects.

A Report On Fluctuating Free Convection Flow Of Heat Absorbing Viscoelastic Dusty Fluid Past In A Horizontal Channel With MHD Effect

The free convective unsteady fluctuating, MHD flow of electrically conducting viscoelastic dusty fluid in a channel-driven with the impact of oscillating pressure gradient and the motion of the upper plate has been studied in this article. The noteworthy heat generation/absorption has also taken into account, the heat generation established the mechanism of heat transfer by both the momentum of fluid and the motion of dust particle and absorption of heat by the dust particle is because of conduction. The coupled governing partial differential equations are reduced to the ordinary differential equation through the assumed periodic solutions. Analytical solutions for the velocity of the fluid as well as the velocity of dust particles and for energy equation of the fluid and for dust particles are obtained by using Poincare-Light Hill Perturbation Technique. The influence of various parameters of interest is discussed on the velocity and temperature profiles of the fluid and particles. The evolution of fluid-phase and dusty-phase with dual behavior of the magnetic parameter for both boundary layer and free stream velocities has been discussed. The boundary layer velocity decreased with an increase in magnetic parameter, while at the free stream flow, the result is quite opposite. The above result of magnetic field is worthwhile and can be used to control the boundary layer thickness. The current work also concludes that by increasing the Peclet number and concentration of the dust particles retards the boundary layer velocity. Furthermore, various physical parameters like coefficient of heat absorption, concentration of the dust particles, peclet number, magnetic parameter, and temperature relaxation time parameter retard the motion of dusty-phase, while Grashof number enhances the flow of dusty-phase. Other properties of fluid, which have great importance for engineers are, the rate of heat transfer and skin friction. It is shown in Table 1 that by increasing the value of Peclet number from 1 to 2 it increases the rate of heat transfer from 1.3263 to 1.3387. Furthermore, Table 2 shows that by increasing the concentration parameter from 2 to 4 the skin friction increases from 2.3872 to 4.7799.

New traveling wave solutions of MHD micropolar fluid in porous medium

This paper aims to determine the exact solutions of non-Newtonian fluid namely micropolar fluid with MHD in a porous medium by traveling wave method. The governing equations of incompressible micropolar fluid with MHD in a porous medium are non-linear PDEs reduced to ODEs through wave parameter ξ=mx+ny+Ut. The set of new exact solutions are determined for five different cases. In special cases, the solution for micropolar fluid with and without MHD and porous effects can also be obtained from general solutions. Furthermore, these solution reduces to a Newtonian solution if we put vortex viscosity κ→0. Finally, the influence of the material and other parameters of interest on the fluid motion, as well as a comparison among micropolar and Newtonian fluids is also analyzed by 2D and 3D graphical illustrations.

MHD fractionalized Jeffrey fluid over an accelerated slipping porous plate

AbstractThe primary target of this paper is to obtain the analytic solutions for the incompressible unsteady flow of fractionalized MHD Jeffrey fluid over an accelerating porous plate with linear slip effect is assumed between fluid and the plate. The governing equations of Jeffrey fluid are developed by fractional calculus approach. The velocity distribution and its corresponding shear stress both are obtained in terms of generalized M-function by using Laplace transform technique and considering all initial and boundary conditions. We have also discussed that obtained results of fractionalized MHD Jeffrey fluid for different cases for instance, with and without slip effects, with and without MHD and porosity effects. The influence of the different parameters affected on the flow characteristic is deliberated with the help of graphs. Finally, the analysis among different fluid models exhibits by graphical illustrations.

A Novel Investigation and Hidden Effects of MHD and Thermal Radiations in Viscous Dissipative Nanofluid Flow Models

Hidden effects of MHD and thermal radiations for a viscous dissipative nanofluids (Al_2 O_3-H_2 O, and γAl_2 O_3-H_2 O) are taken under consideration. The models are formulated by implementing the suitable similarity transformations. Then, two models are discussed mathematically by using RK scheme together with shooting method. The results for flow regimes, coefficient of skin friction, thermophysical characteristics and heat transfer coefficient are pictured and discussed comprehensively by changing the pertinent flow parameters. It is observed that the nanofluids velocity increases abruptly for higher Hartree pressure gradient. For assisting flow situation, the velocity F'(η) increases and abrupt decreasing behavior is examined for opposing flow case. The composition of Al_2 O_3-H_2 O, and γAl_2 O_3-H_2 O becomes more dense for high volume fraction therefore, drops in the velocity field is noted. The temperature of Al_2 O_3-H_2 O, and γAl_2 O_3-H_2 O rises rapidly by varying opposing flow parameter γ<0 and high volume fraction ϕ. Also, the temperature β(η) declines abruptly for parameter λ.

MHD effects on non-Newtonian fluid with heat and mass transfer over exponentially extending inclined surface

MHD effects on non-Newtonian fluid with heat and mass transfer over exponentially extending inclined surface

MHD effect on mixed convection of annulus circular enclosure filled with Non-Newtonian nanofluid

The fluid flow and mixed convection heat transfer of a non-Newtonian (Cu–water) nanofluid-filled circular annulus enclosure in a magnetic field are investigated numerically for a two-dimensional, steady-state, incompressible, laminar flow using the Galerkin finite element method (GFEM). The Prandtl number (Pr = 6.2) and Grashof number (Gr = 100) are assumed to be constants, whereas the Richardson number varies within a range of 0 ≤ Ri ≤ 1, the Hartman number within a range of 0 ≤ Ha ≤60, the Power law index within a range of 0.2 ≤ n ≤ 1.4, and the volume fraction within a range of 0 ≤ φ ≤ 1. The enclosure consists of an outer rotating cylinder that is kept at a cold temperature (Tc) and an inner non-rotating cylinder kept at a hot temperature (Th). The ratio of the inner circular diameter to the annulus space length is kept constant at 2. The results depict that the stream function increases with increasing power law index, even up to n = 1, which causes the fluid to behave as a Newtonian fluid. The magnetic field has a critical impact on the fluid flow pattern. The average Nusselt number increases with decreasing Richardson number, owing to the improved heat transfer by forced convection.

MHD effects on the channel flow of a fractional viscous fluid through a porous medium: An application of the Caputo-Fabrizio time-fractional derivative

This research article considers the exact solutions and theoretical aspects of the channel flow of a fractional viscous fluid which is electrically conducting and flowing through a porous medium. Joint Laplace and Fourier transform techniques are used to solve the momentum equation. The Caputo-Fabrizio time fractional derivative is used in the constitutive equations. Exact solutions for an arbitrary velocity are obtained, and then in the limiting cases over a bottom plate three types of flow are considered: that is, the impulsive, accelerating and oscillating motion of the fluid. The case where the flow of the fractional fluid is unaffected by the side walls, is correspondingly taken into account. For oscillating flow the solutions are separated into steady and transient parts for both sine and cosine oscillations. Moreover these solutions are captured graphically, and the effect of the Reynolds number “Re”, fractional parameter “α”, effective permeability “Keff” and the time “t”, on the fluid's motion are observed.

Heat transfer analysis of ethylene glycol-based Casson nanofluid around a horizontal circular cylinder with MHD effect

In this work, efforts were taken to investigate the free convection of ethylene glycol-based Casson nanofluid and it is affected by a magnetic field about a horizontal circular cylinder. Three different types of oxide nanoparticles were used along with constant wall temperature. Tiwari and Das's nanofluid model was used to investigate the MHD free convective flow of Casson nanofluid. The transformed governing PDEs were solved via the Keller box method. Numerical and graphical findings were acquired by using MATLAB software, in addition to studying and analyzing the influence of related parameters, on the velocity, temperature, local skin friction coefficient, and local Nusselt number. The results demonstrate that copper oxide ethylene glycol-based Casson nanofluid has the lowest local Nusselt number, velocity and, it has the highest temperature. Also, our results were in excellent agreement with prior published results.

Natural Convection MHD Effect on Heat Transfer in Vertical Cylinder

In this paper, natural convection MHD effect on Heat transfer in vertical cylinder is analyzed. Firstly heat transfer equation and convert it in dimensionless form by introducing dimensionless variables has considered. By use of finite Hankel and inverse Hankel transforms in dimensionless heat transfer equation, the values of temperature and Nusselt number is obtained. Finally, graphical representation is used to study the effect of Prandtl number pr on temperature and Nusselt number Nu. It is observed that the fluid at the center region of the cylinder is not heated for value of Prandtl number Pr greater than 1.7 for small values of t.

MHD Effects on Ciliary-Induced Peristaltic Flow Coatings with Rheological Hybrid Nanofluid

Present theoretical investigation is a mathematical illustration of an application to endoscopy by incorporating hybrid nanoparticles and an induced magnetic field with a rheological fluid model for more realistic results. Rheological fluid behavior is characterized by the Ostwald-de-Waele power-law model. A hybrid nanofluid mechanism is considered comprising platelet-shaped nanoparticles since nanoparticles are potential drug transportation tools in biomedical applications. Moreover, ciliary activity is encountered regarding their extensive applications in performing complex functions along with buoyancy effects. An endoscope is inserted inside a ciliated tube and peristalsis occurred due to ciliary activity in the gap between tube and endoscope. A non-Newtonian model is developed by mathematical formulation which is tackled analytically using homotopy analysis. The outcomes are interpreted graphically along with the pressure rise and streamlining configuration for the case of negligible inertial forces and long wavelength. A three-dimensional graphical interpretation of axial velocity is studied as well. Moreover, tables are prepared and displayed for a more physical insight.

Keller-box analysis of inclination flow of magnetized Williamson nanofluid

The main purpose of the current investigation is to report the numerical solution of the thermal radiations and MHD effect on the laminar flow of an incompressible Williamson nanofluid. Further, the effect of Brownian motion and thermophoresis on the flow field are considered. Compatible similarities are implemented on the flow equations to obtain the nonlinear ordinary differential equations. The numerical solution of the governing differential equations is obtained via the Keller box scheme. Findings exhibit that the energy and mass transport moderates with the growth of inclination factor along with Brownian motion effect. The temperature profile increases with the radiations factor attains a peak, which is useful for the industrial procedures. The velocity profile increases for the higher magnitudes of buoyancy factor.

A Finite Element Simulation of the Active and Passive Controls of the MHD Effect on an Axisymmetric Nanofluid Flow with Thermo-Diffusion over a Radially Stretched Sheet

The present study investigated the steady magnetohydrodynamics of the axisymmetric flow of a incompressible, viscous, electricity-conducting nanofluid with convective boundary conditions and thermo-diffusion over a radially stretched surface. The nanoparticles’ volume fraction was passively controlled on the boundary, rather than actively controlled. The governing non-linear partial differential equations were transformed into a system of nonlinear, ordinary differential equations with the aid of similarity transformations which were solved numerically, using the very efficient variational finite element method. The coefficient of skin friction and rate of heat transfer, and an exact solution of fluid flow velocity, were contrasted with the numerical solution gotten by FEM. Excellent agreement between the numerical and exact solutions was observed. The influences of various physical parameters on the velocity, temperature, and solutal and nanoparticle concentration profiles are discussed by the aid of graphs and tables. Additionally, authentication of the convergence of the numerical consequences acquired by the finite element method and the computations was acquired by decreasing the mesh level. This exploration is significant for the higher temperature of nanomaterial privileging technology.

Radiation and MHD effects on an oscillatory flow of a Jeffrey fluid in a circular tube

Radiation and MHD effects on an oscillatory flow of a Jeffrey fluid in a circular tube

Influences of electrical MHD and Hall current on squeezing nanofluid flow inside rotating porous plates with viscous and joule dissipation effects

Nanofluids have the ability to flow smoothly in micro-cavities in addition with scattering of the nanoparticles. Because of the good convection between nanoparticles and the base fluid, nanofluids can achieve a good thermal conductivity. The main advantages of adding nanosize particles with base fluid are to improve the ability of storing heat, effective surface area, heat transmission, collisions and interaction among the nanoparticles. The main aim of this research work is to examine the steady and incompressible nanofluid flow between parallel rotating plates. Viscose and joule dissipation effects are taken into account. To our knowledge, impact of electrical MHD and Hall effect with Cattaneo–Christov heat flux on the squeezing 3-D flow nanofluid between parallel rotating plates are not examined yet. Heat in the form of Cattaneo–Christov heat flux is applied. We used similarity transformations to transform the primary equations to a system of ordinary differential equations (ODEs). These ODEs are then solved through the standard procedure of homotopy analysis technique. The skin friction and Nusselt number are numerically tabulated under the influence of some focused parameters. The effects produced by different parameters on the velocity (components) and temperature profiles are graphically depicted and explained in a bit detail.

Flow past a vertical porous surface under fluctuating thermal and mass diffusion with MHD effects

This paper is examined with reference to critical parameters in the case of free MHD convection flow on a vertical porous surface under the fluctuating thermal and mass diffusion. An attempt has been made to understand the effects of the various critical parameters that appear in field equations and their effects over velocity field. It is noticed that, the prandtl number and velocity are inversely related. Moreover, it is observed that as the prandtl number increases, there is a decrease in the velocity and also back flow is observed. Even when the pore size of the bounding surface is decreased significant change in the velocity profiles is seen. Moreover, it is noticed that the prandtl number and temperature are directly proportional to each other.

MHD free convective heat and mass transfer flow of dissipative Casson fluid with variable viscosity and thermal conductivity effects

In this paper, the Cattaneo–Christov heat flux relocation paradox on Casson fluid with MHD and dissipative effects was considered. The buoyancy and heat generation effects were believed to be responsible for the natural convection, while variable properties were perceived as temperature-dependent linear function. Under the given assumptions, the governing system of equations was formulated and transformed. Hence, the Chebyshev collocation spectral approach was therefore employed to achieve an approximate solution. However, the behaviour of temperature-dependent variability establishes the relationship between the boundary layer flow of plastic dynamic viscosity and the Casson fluid. Furthermore, it was observed that a corresponding increase in the stretching index increases the skin friction and decreases the energy and mass gradient accordingly. The relocation phenomenon contributes to a decrease in the thermal process, while the temperature gradient attained maximum within variation of the Casson parameter.

Analysis of Mhd Effect on Rayleigh Step Slider Bearing Lubricated with Couple-Stress Fluids

Analysis of Mhd Effect on Rayleigh Step Slider Bearing Lubricated with Couple-Stress Fluids