6533b7ddfe1ef96bd127473c
RESEARCH PRODUCT
Thermophoretic separation of ultrafine particles in ferrofluids in thermal diffusion column under the effect of an MHD convection
Stefan OdenbachElmars Blumssubject
Fluid Flow and Transfer ProcessesConvectionFerrofluidBuoyancyMaterials scienceConvective heat transferMechanical EngineeringThermodynamicsengineering.materialCondensed Matter PhysicsThermal diffusivityThermophoresisPhysics::Fluid DynamicsengineeringParticleHydrodynamic theorydescription
The aim of the paper is to evaluate the Soret coeAcient ST of colloidal particles in ferrofluids from measurements of an unsteady particle separation in a flat thermodiAusion column. The column theory is modified taking into account MHD eAects of thermal convection aAected by a concentration buoyancy force. It is shown that the Hartmann eAect, not only in hydrocarbon based colloids but also in ionic magnetic fluids of relatively high electric conductivity, does not influence significantly the particle separation dynamics. From measurements, positive values of ST of surfacted particles in tetradecane based colloids are calculated. An anisotropy of the Soret eAect in the presence of a uniform magnetic field is experimentally established. The obtained results agree qualitatively well with the authors hydrodynamic theory of particle thermomagnetophoresis. # 2000 Elsevier Science Ltd. All rights reserved.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2000-05-01 | International Journal of Heat and Mass Transfer |