Growth rates of Bénard-Marangoni convection in a fluid layer in the presence of a magnetic field

2004 ◽  
Vol 15 (1) ◽  
pp. 22-27 ◽  
Author(s):  
Norihan Md Arifin ◽  
Ishak Hashim
Keyword(s):  
Magnetic Field ◽  
Growth Rates ◽  
Marangoni Convection ◽  
Fluid Layer

Combined effects of nonuniform temperature gradients and heat source on double diffusive Benard-Marangoni convection in a porous-fluid system in the presence of vertical magnetic field

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
N. Manjunatha ◽  
R. Sumithra ◽  
R.K. Vanishree
Keyword(s):  
Magnetic Field ◽  
Heat Source ◽  
Marangoni Number ◽  
Marangoni Convection ◽  
Fluid Layer ◽  
Temperature Gradients ◽  
Vertical Magnetic Field ◽  
Nonuniform Temperature ◽  
Fluid System ◽  
Double Diffusive

The physical configuration of the problem is a porous-fluid layer which is horizontally unbounded, in the presence of uniform heat source/sink in the layers enclosed by adiabatic and isothermal boundaries. The problem of double diffusive Bènard-Marangoni convection in the presence of vertical magnetic field is investigated on this porous-fluid system for non-Darcian case and is subjected to uniform and nonuniform temperature gradients. The eigenvalue, thermal Marangoni number is obtained in the closed form for lower rigid and upper free with surface tension velocity boundary conditions. The influence of various parameters on the Marangoni number against thermal ratio is discussed. It is observed that the heat absorption in the fluid layer and the applied magnetic field play an important role in controlling Benard-Marangoni convection. The parameters which direct this convection are determined and the effect of porous parameter is relatively interesting.

The effect of magnetic field on Marangoni convection in a nanofluid layer with internal heat source

2017 ◽  
Author(s):  
Izzati Khalidah Khalid ◽  
Nor Fadzillah Mohd Mokhtar ◽  
Zailan Siri ◽  
Zarina Bibi Ibrahim ◽  
Siti Salwa Abd Gani
Keyword(s):  
Magnetic Field ◽  
Heat Source ◽  
Marangoni Convection ◽  
Internal Heat ◽  
Internal Heat Source

Influences of Marangoni Convection and Variable Magnetic Field Hybrid Nanofluid Thin Film Flow past a Stretching Surface

2021 ◽  
Author(s):  
Noor Wali Khan ◽  
Arshad Khan ◽  
Muhammad Usman ◽  
Taza Gul ◽  
Abir Mouldi ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Thin Film ◽  
Film Flow ◽  
Marangoni Convection ◽  
Flow System ◽  
Thermal Characteristics ◽  
Variable Magnetic Field ◽  
Current Work ◽  
Hybrid Nanofluid ◽  
Thin Film Flow

Abstract The investigations about thin-film flow play a vital role in the field of optoelectronics and magnetic devices. Thin films are reasonably hard and thermally stable but are more fragile. The thermal stability of thin film can be further improved by incorporating the effects of nanoparticles. In the current work, a stretchable surface is considered upon which hybrid nanofluid thin-film flow is taken into account. The idea of augmenting heat transmission is focused in current work by making use of hybrid nanofluid. The flow is affected by variations in the viscous forces along with viscous dissipation effects and Marangoni convection. A time-constrained magnetic field is applied in the normal direction to the flow system. The equations governing the flow system are shifted to a non-dimensional form by applying similarity variables. The homotopy analysis method (HAM) has been employed to find the solution of resultant equations. It has been noticed in this study that, the flow characteristics decline with augmentation in magnetic, viscosity, and unsteadiness parameters while grow up with enhancing values of thin-film parameter. Thermal characteristics are supported by the growing values of the Eckert number and unsteadiness parameter while opposed by the viscosity parameter and Prandtl number. The numerical impact of different emerging parameters upon skin friction and Nusselt number has been calculated in tabular form. A comparison of current work with established result has carried out with a good agreement in both results.

Ferrohydrodynamic Capillary Convection

2018 ◽  
Vol 11 (2) ◽  
Author(s):  
Francisco J. Arias ◽  
Salvador A. De Las Heras
Keyword(s):  
Magnetic Field ◽  
Surface Tension ◽  
Concentration Gradient ◽  
Deductive Reasoning ◽  
Marangoni Convection ◽  
Marangoni Effect ◽  
Magnetic Fluids ◽  
Homogeneous Magnetic Field ◽  
Gradient Field ◽  
Two Fluids

Abstract In this work, consideration is given to capillary convection on ferrofluids from the concentration gradient induced when a nonhomogeneous magnetic field is applied. It is known that mass transfer along an interface between two fluids can appear due to a gradient of the surface tension in the so-called Marangoni effect (or Gibbs–Marangoni effect). Because the surface tension is both thermal and concentration dependent, Marangoni convection can be induced by either a thermal or a concentration gradient, where in the former case, it is generally referred as thermocapillary convection. Now, it has been theoretically and experimentally demonstrated that a ferrofluid under the action of a non-homogeneous magnetic field can induce a concentration gradient of suspended magnetic nanoparticles, and also the effect of Fe3O4 nanoparticles on the surface tension has been measured. Therefore, by deductive reasoning and taking into account the above mentioned facts, it is permissible to infer ferrohydrodynamic capillary convection on magnetic fluids under the presence of a magnetic gradient field. Utilizing a simplified physical model, the phenomenon was investigated and it was found that ferrohydrodynamic-Marangoni convection could be induced with particle size in the range up to 10 nm, which is the range of magnetic fluids to escape magnetic agglomeration.

Sign in / Sign up

Export Citation Format

Share Document