Magnetophoresis, sedimentation, and diffusion of particles in concentrated magnetic fluids / Pshenichnikov Alexander F.,Elfimova Ekaterina A.,Ivanov Alexey O. // JOURNAL OF CHEMICAL PHYSICS. - 2011. - V. 134, l. 18.

ISSN/EISSN:

0021-9606 / нет данных

Type:

Article

Abstract:

A dynamic mass transfer equation for describing magnetophoresis, sedimentation, and gradient diffusion of colloidal particles in concentrated magnetic fluids has been derived. This equation takes into account steric, magnetodipole, and hydrodynamic interparticle interactions. Steric interactions have been investigated using the Carnahan-Starling approximation for a hard-sphere system. In order to study the effective interparticle attraction, the free energy of the dipolar hard-sphere system is represented as a virial expansion with accuracy to the terms quadratic in particle concentration. The virial expansion gives an interpolation formula that fits well the results of computer simulation in a wide range of particle concentrations and interparticle interaction energies. The diffusion coefficient of colloidal particles is written with regard to steric, magnetodipole and hydrodynamic interactions. We thereby laid the foundation for the formulation of boundary-value problems and for calculation of concentration and magnetic fields in the devices (for example, magnetic fluid seals and acceleration sensors), which use a concentrated magnetic fluid as a working fluid. The Monte-Carlo methods and the analytical approach are employed to study the magnetic fluid stratification generated by the gravitational field in a cylinder of finite height. The coefficient of concentration stratification of the magnetic fluid is calculated in relation to the average concentration of particles and the dipolar coupling constant. It is shown that the effective particle attraction causes a many-fold increase in the concentration inhomogeneity of the fluid if the average volume fraction of particles does not exceed 30\%. At high volume concentrations steric interactions play a crucial role. (C) 2011 American Institute of Physics. {[}doi:10.1063/1.3586806]

Author keywords:

BROWNIAN DIFFUSION; DIPOLAR SYSTEMS; FERROCOLLOIDS; EQUILIBRIUM; SUSCEPTIBILITY; DISPERSIONS; SIMULATION; FIELD

DOI:

10.1063/1.3586806

Web of Science ID:

ISI:000290589900032

Соавторы в МНС:

Другие поля

Поле	Значение
Month	MAY 14
Publisher	AMER INST PHYSICS
Address	CIRCULATION \& FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA
Language	English
Article-Number	184508
Keywords-Plus	BROWNIAN DIFFUSION; DIPOLAR SYSTEMS; FERROCOLLOIDS; EQUILIBRIUM; SUSCEPTIBILITY; DISPERSIONS; SIMULATION; FIELD
Research-Areas	Chemistry; Physics
Web-of-Science-Categories	Chemistry, Physical; Physics, Atomic, Molecular \& Chemical
Author-Email	Ekaterina.Elfimova@usu.ru
ResearcherID-Numbers	Elfimova, Ekaterina/P-5003-2016 Pshenichnikov, Alexander/F-9511-2013 Ivanov, Alexey/E-4442-2011
ORCID-Numbers	Ivanov, Alexey/0000-0001-8239-4039 Elfimova, Ekaterian/0000-0002-8941-8184
Funding-Acknowledgement	Russian Foundation for Basic Research {[}10-01-96038]; Department of Energetic, Machine building, Mechanics and Control Processes RAS {[}09-T-1-1005]; Federal Target Program ``Scientific and Academic - Teaching Staff of Innovative Russia{''}; RF {[}MK-1673.2010.2]
Funding-Text	The work was supported by the Russian Foundation for Basic Research (Grant No. 10-01-96038); the Department of Energetic, Machine building, Mechanics and Control Processes RAS (Project No. 09-T-1-1005); Federal Target Program ``Scientific and Academic - Teaching Staff of Innovative Russia{''} in 2009-2013 and Grant of President of RF MK-1673.2010.2.
Number-of-Cited-References	31
Usage-Count-Last-180-days	4
Usage-Count-Since-2013	22
Journal-ISO	J. Chem. Phys.
Doc-Delivery-Number	763WH