Numerical study of equilibrium forms of magnetic fluid including magnetic field disturbances

A numerical analysis is conducted in order to study the flow state and thermal characteristics of a magnetic fluid heat transport device. A simple geometrical model of the device is considered in the present numerical study. The highly simplified marker-and-cell (HSMAC) method is adopted for the numerical analysis, where the transient solutions are obtained in the two-dimensional axisymmetric computational plane. From results of the numerical calculation it can be shown that the vortex zone appears when a magnetic field is applied and the configuration of flow associated with the vortex zone changes for variation in the magnetic field, increasing or decreasing the heat transport capability dependent upon the conditions of the device.

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A NUMERICAL STUDY ON THE MAGNETIC FLUID FLOW IN A CHANNEL SURROUNDING A PERMANENT MAGNET UNDER TEMPERATURE FIELD

Modern Physics Letters B ◽

10.1142/s0217984907013535 ◽

2007 ◽

Vol 21 (19) ◽

pp. 1271-1283 ◽

Cited By ~ 1

Author(s):

X. L. LI ◽

K. L. YAO ◽

Z. L. LIU

Keyword(s):

Magnetic Field ◽

Permanent Magnet ◽

Magnetic Fluid ◽

Numerical Study ◽

Drug Carrier ◽

Temperature Fields ◽

Gradient Magnetic Field ◽

Local Skin ◽

High Gradient ◽

Magnetic Source

It was investigated that the magnetic fluid which can be the carrier of magnetic particles or magnetic drug carrier particles (MDCP) flows surrounding a permanent magnet in a channel under the influence of high gradient magnetic field and the temperature difference between upper and lower boundaries of the channel. It is considered that the magnetization of the fluid varies linearly with temperature and magnetic field intensity. The numerical solution of above model is described by a coupled and nonlinear system of PDEs. Results indicate that the presence of magnetic and temperature fields appreciably influence the flow field; vortexes arise almost around the magnetic source and also appear near the upper left and lower right boundaries. The temperature, local skin friction coefficient and rate of heat transfer are all affected by the magnitude and position of the magnetic source, they fluctuate evidently near the high gradient magnetic field area.

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Numerical study of forced and free convective boundary layer flow of a magnetic fluid over a flat plate under the action of a localized magnetic field

Zeitschrift für angewandte Mathematik und Physik ◽

10.1007/s00033-009-0054-7 ◽

2010 ◽

Vol 61 (5) ◽

pp. 929-947 ◽

Cited By ~ 9

Author(s):

E. E. Tzirtzilakis ◽

N. G. Kafoussias ◽

A. Raptis

Keyword(s):

Magnetic Field ◽

Boundary Layer ◽

Flat Plate ◽

Magnetic Fluid ◽

Convective Boundary Layer ◽

Boundary Layer Flow ◽

Numerical Study ◽

Convective Boundary ◽

Layer Flow ◽

Localized Magnetic Field

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NUMERICAL STUDY OF THE ROSENSWEIG INSTABILITY IN A MAGNETIC FLUID SUBJECT TO DIFFUSION OF MAGNETIC PARTICLES

Mathematical Modelling and Analysis ◽

10.3846/1392-6292.2010.15.223-233 ◽

2010 ◽

Vol 15 (2) ◽

pp. 223-233 ◽

Cited By ~ 3

Author(s):

Olga Lavrova ◽

Viktor Polevikov ◽

Lutz Tobiska

Keyword(s):

Magnetic Field ◽

Free Surface ◽

Magnetic Fluid ◽

Magnetic Particles ◽

Numerical Study ◽

Fluid Layer ◽

Classical Problem ◽

Parametric Representation ◽

Field Configuration ◽

Wide Range

The present study is devoted to the classical problem on stability of a magnetic fluid layer under the influence of gravity and a uniform magnetic field. A periodical peak‐shaped stable structure is formed on the fluid surface when the applied magnetic field exceeds a critical value. The mathematical model describes a single peak in the pattern assuming axial symmetry of the peak shape. The field configuration in the whole space, the magnetic particle concentration inside the fluid and the free surface structure are unknown quantities in this model. The unknown free surface is treated explicitly, using a parametric representation with respect to the arc length. The nonlinear problem is discretized by means of a finite element method for the Maxwell's equations and a finite‐difference method for the free surface equations. Numerical modelling allows to get over‐critical equilibrium free surface shapes in a wide range of applied field intensities. Our numerical results show a significant influence of the particle diffusion on the overcritical shapes.

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