scholarly journals Flow and heat transfer of MHD graphene oxide-water nanofluid between two non-parallel walls

2017 ◽  
Vol 21 (5) ◽  
pp. 2095-2104 ◽  
Author(s):  
Mohammadreza Azimi ◽  
Rouzbeh Riazi
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Graphene Oxide ◽  
Volume Fraction ◽  
Flow And Heat Transfer ◽  
S Parameter ◽  
Non Linear ◽  
Optimal Homotopy Asymptotic Method ◽  
Prandtl Numbers ◽  
Linear Differential

The steady 2-D heat transfer and flow between two non-parallel walls of a graphene oxide nanofluid in presence of uniform magnetic field are investigated in this paper. The analytical solution of the non-linear problem is obtained by Galerkin optimal homotopy asymptotic method. At first a similarity transformation is used to reduce the partial differential equations modeling the flow and heat transfer to ordinary non-linear differential equation systems containing the semi angle between the plate?s parameter, Reynolds number, the magnetic field strength, nanoparticle volume fraction, Eckert and Prandtl numbers. Finally, the obtained analytical results have been compared with results achieved from previous works in some cases.

scholarly journals Effect of magnetic field on the steady nanofluid flow past obstacle

2021 ◽  
Vol 22 (3) ◽  
pp. 535-542
Author(s):  
Yacine Khelili ◽  
Rafik Bouakkaz
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Laminar Flow ◽  
Hartmann Number ◽  
Volume Fraction ◽  
Transverse Magnetic ◽  
Heated Wall ◽  
Cylinder Wake ◽  
Flow And Heat Transfer ◽  
Model Transition

The fluid flow and heat transfer of a nanofluid past a circular cylinder in a rectangular duct under a strong transverse magnetic field is studied numerically using a quasitwo-dimensional model. Transition from laminar flow with separation to creeping laminar flow is determined as a function of Hartmann number and the volume fraction of nanoparticle, as are critical Hartmann number, and the heat transfer from the heated wall to the fluid. Downstream cross-stream mixing induced by the cylinder wake was found to increase heat transfer. The successive changes in the flow pattern are studied as a function of the Hartmann number. Suppression of vortex shedding occurs as the Hartmann number increases.

Coupled flow and heat transfer of power-law Nanofluids on a non-isothermal rough rotary disk subject to magnetic field

2021 ◽  
Author(s):  
Yunxian Pei ◽  
Xuelan Zhang ◽  
Liancun Zheng ◽  
Xinzi Wang
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Power Law ◽  
Numerical Solutions ◽  
Volume Fraction ◽  
Rotating Disk ◽  
Coupled Flow ◽  
Friction Coefficients ◽  
Nanoparticle Shape ◽  
Flow And Heat Transfer

Abstract In this paper, we study coupled flow and heat transfer of power-law nanofluids on a non-isothermal rough rotating disk subject to a magnetic field. The problem is formulated in terms of specified curvilinear orthogonal coordinate system. An improved BVP4C algorithm is proposed and numerical solutions are obtained. The influence of volume fraction, types and shapes of nanoparticles, magnetic field and power-law index on the flow and heat transfer behavior are discussed.<br/>Results show that the power-law exponents (PLE), nanoparticle volume fraction (NVF) and magnetic field inclination angle (MFIA) are almost no effects on velocities in wave surface direction, but have small or significant effects on azimuth direction. NVF have remarkable influence on local Nusselt number (LNN) and friction coefficients (FC) in radial and azimuth directions (AD). LNN increases with NVF while FC in AD decrease. The types of nanoparticles, magnetic field strength and inclination have small effects on LNN, but they have remarkable effects on the friction coefficients with positively correlated while the inclination is negatively correlated with heat transfer rate. The size of the nanoparticle shape factor is positively correlated with LNN.

Analytical Investigation of Nusselt Number and Skin Friction of Fluid Flow Over a Stretching Sheet Using Optimal Homotopy Asymptotic Method

2020 ◽  
Vol 12 (5) ◽  
pp. 657-661
Author(s):  
Zohreh Aliannejadi
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Boundary Layer ◽  
Nusselt Number ◽  
Fluid Flow ◽  
Differential Equations ◽  
Skin Friction ◽  
Flow And Heat Transfer ◽  
Optimal Homotopy Asymptotic Method ◽  
The Magnetic Field

In many cases such as production of metal sheets, the behavior of fluid flow and heat transfer in the neighborhood of a hot plate is very important. The CFD simulation of fluid flow is a widespread study that reveals detail information about the fluid flow in the calculated domain. In this study, the flow and heat transfer of a specific fluid in the above area of a stretching plate is examined analytically to find the variation of skin friction and Nusselt number. For this purpose, the similarity transformations can be employed to achieve the ordinary differential equations from the governing partial differential equations. The optimal homotopy asymptotic method (OHAM) is used to solve the ordinary differential equations which is applicable in solving of nonlinear equations. The effects of magnetic field on the analytical results from solving the equations are evaluated in detail. It is found that the thickness of the flow boundary layer decreases and the thickness of the thermal boundary layer increases by increasing in the magnetic field. Moreover, the Nusselt number is lower and skin friction is higher for the higher values of the magnetic field.

Magneto-hydrodynamic Blasius flow and heat transfer from a flat plate in the presence of suspended carbon nanofluids

2017 ◽  
Vol 232 (1) ◽  
pp. 31-40
Author(s):  
Mahantesh M Nandeppanavar ◽  
Rama Subba Reddy Gorla ◽  
S Shakunthala
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
External Magnetic Field ◽  
Flat Plate ◽  
Linear Partial Differential Equation ◽  
Governing Equations ◽  
Linear Ordinary Differential Equations ◽  
Similarity Transformations ◽  
Flow And Heat Transfer ◽  
Non Linear

In this article, we have discussed the effect of external magnetic field and other governing parameters on the flow and heat transfer in the presence of suspended carbon nanotubes over a flat plate. The governing equations of flow and heat transfer are derived from the Navier–Stokes and Prandtl boundary layer concept. The derived governing equations of flow and energy are non-linear partial differential equation, and these equations are converted into non-linear ordinary differential equations with corresponding boundary conditions using some suitable similarity transformations and are solved numerically using fourth-order Runge–Kutta method with efficient shooting technique. Effects of governing parameters on flow and heat transfer are shown through various graphs and explained with physical interpretation in detail. This study has applications in glass-fiber production and technology. On observing the results of this study, we can conclude that external magnetic field shows opposite behaviors on velocity and temperature and it enhances the rate of heat transfer.

Effect of MHD on the flow and heat transfer characteristics of nanofluid in a grooved channel with internal heat generation

2019 ◽  
Vol 29 (4) ◽  
pp. 1403-1431 ◽  
Author(s):  
Mohammad Sadegh Dehghani ◽  
Davood Toghraie ◽  
Babak Mehmandoust
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Heat Generation ◽  
Volume Fraction ◽  
Convective Heat Transfer Coefficient ◽  
Internal Heat ◽  
Reynolds Numbers ◽  
Internal Heat Generation ◽  
Content Type ◽  
Flow And Heat Transfer

Purpose The purpose of this study is numerical simulation of magnetohydrodynamics (MHD) water–Al2O3 nanofluid mixed convection in a grooved channel with internal heat generation in solid cylinders. Simulations were carried out at Reynolds numbers 50 ≤ Re ≤ 100, Hartmann numbers 0 ≤ Ha ≤ 15, Grashof numbers 5,000 ≤ Gr ≤ 10−4 and volume fraction 0 ≤ φ ≤ 0.04. The effect of Reynolds number and the influence of magnetic field and pressure drop on convective heat transfer coefficient were studied in different volume fractions of nanoparticles at different Reynolds numbers. Design/methodology/approach The results show that average Nusselt number increases by increasing Reynolds and Hartman numbers. Also, when Hartman number increases, velocity profile becomes asymmetric. Pressure distribution shows that magnetic field applies Lorentz force at opposite direction of the flow, which causes asymmetric distribution of pressure. As a result, pressure in the upper half of the cylinder is higher than the lower half. Finally, velocity and temperature contours along the channel for different Hartmann numbers, volume fraction 3 per cent, Re = 50 and 100 and Gr = 10,000, are presented. Findings The effect of Reynolds number and the influence of magnetic field and pressure drop on convective heat transfer coefficient were studied in different volume fractions of nanoparticles at different Reynolds numbers. Originality/value Effect of MHD on the flow and heat transfer characteristics of Water–Al2O3 nanofluid in a grooved channel with internal heat generation in solid cylinders.

scholarly journals Magneto-Hydro Dynamic Flow and Heat Transfer of Nonnewtonian Power-Law Fluid Over a Non-Linear Stretching Surface with Viscous Dissipation

2014 ◽  
Vol 19 (2) ◽  
pp. 259-273 ◽  
Author(s):  
N. Kishan ◽  
P. Kavitha
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Differential Equations ◽  
Ordinary Differential Equations ◽  
Power Law ◽  
Transverse Magnetic ◽  
Stretching Surface ◽  
Power Law Fluid ◽  
Flow And Heat Transfer ◽  
Non Linear

Abstract A fluid flow and heat transfer analysis of an electrically conducting non-Newtonian power law fluid flowing over a non-linear stretching surface in the presence of a transverse magnetic field taking into consideration viscous dissipation effects is investigated. The stretching velocity, the temperature and the transverse magnetic field are assumed to vary in a power-law with the distance from the origin. The flow is induced due to an infinite elastic sheet which is stretched in its own plane. The governing equations are reduced to non-linear ordinary differential equations by means of similarity transformations. By using quasi-linearization techniques first linearize the non linear momentum equation is linearized and then the coupled ordinary differential equations are solved numerically by an implicit finite difference scheme. The numerical solution is found to be dependent on several governing parameters, including the magnetic field parameter, power-law index, Eckert number, velocity exponent parameter, temperature exponent parameter, modified Prandtl number and heat source/sink parameter. A systematic study is carried out to illustrate the effects of these parameters on the fluid velocity and the temperature distribution in the boundary layer. The results for the local skin-friction coefficient and the local Nusselt number are tabulated and discussed.

scholarly journals Fluid Flow and Heat Transfer Analysis of Quadratic Free Convection in a Nanofluid Filled Porous Cavity

2021 ◽  
Vol 39 (3) ◽  
pp. 876-884
Author(s):  
Jino Lawrence ◽  
Vanav Kumar Alagarsamy
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Fluid Flow ◽  
Rayleigh Number ◽  
Convection Heat Transfer ◽  
Darcy Number ◽  
Convection Heat ◽  
Flow And Heat Transfer ◽  
Non Linear ◽  
Convection Parameter

The involvement of non-linear convection effects in a natural convective fluid flow and heat transfer along with the effects of magnetic field in a porous cavity is studied numerically. Cu-water filled cavity of higher temperature at the left wall and lower temperature at the right wall. The governing equations are organized to achieve the required flow by using two-dimensional equations of energy, continuity and momentum. Vorticity-stream function based dimensionless equations are solved using the finite difference techniques. The results are discussed for various dimensionless parameters such as the Darcy number, non-linear convection parameter, Hartmann number, Rayleigh number and solid volume fraction of the nanoparticles. An augment in streamline velocity and convection heat transfer are observed by increasing the Rayleigh number, non-linear convection parameter and Darcy number. The non-linear convection parameter has a lesser effect on the lower Rayleigh numbers. Diminished streamline intensity and reduction in convection heat transfer are noted for an increase in the strength of the applied magnetic field irrespective of the non-linear convection parameter.

Impact of heat generation/absorption on the unsteady magnetohydrodynamic stagnation point flow and heat transfer of nanofluids

2019 ◽  
Vol 30 (2) ◽  
pp. 557-574 ◽  
Author(s):  
Rahimah Jusoh ◽  
Roslinda Nazar ◽  
Ioan Pop
Keyword(s):  
Magnetic Field ◽  
Heat Transfer ◽  
Shear Stress ◽  
Stability Analysis ◽  
Unsteady Flow ◽  
Heat Generation ◽  
Volume Fraction ◽  
Nanoparticle Volume Fraction ◽  
Content Type ◽  
Flow And Heat Transfer

Purpose The purpose of this study is to describe the unsteady three-dimensional magnetohydrodynamic stagnation point flow of nanofluids with heat generation/absorption. Design/methodology/approach The comprehensive numerical simulations in this study accommodate a physical insight into the heat transfer and flow problem. The use of finite difference method through the bvp4c function in Matlab provides the numerical results and graphical illustrations for the heat transfer rate and shear stress. Findings Dual solutions are discovered in this study. Thus, stability analysis is implemented and the first solution complies the stability behavior. Silver nanoparticles dominate the highest thermal conductivity. Accretion of the rate of heat transfer is obtained with an increment in the magnitude of heat absorption, suction parameter and nanoparticle volume fraction. A stronger magnetic field and larger unsteadiness parameter contribute to the increase of the surface shear stress. Practical implications Many practical fluid mechanics problems involve the time-dependent element. Practically, an unsteady flow of nanofluid can be implemented in the micro-manufacturing, periodic heat exchanges process, nano drug delivery system and nuclear reactors. Originality/value In spite of numerous studies on the unsteady flow, none of the researchers combined the effect of heat generation/absorption and magnetic field in the nanofluid model. The behavior of the flow and heat transfer have been analyzed thoroughly with the variations in the unsteadiness parameter, heat source/sink and nanoparticle volume fraction. Moreover, the discovery of dual solutions in this model strengthens the novelty of this study. Subsequently, the implementation of stability analysis leads to a remarkable revelation where the first solution is found to be stable.

Sign in / Sign up

Export Citation Format

Share Document