화학공학소재연구정보센터
Journal of Colloid and Interface Science, Vol.375, 203-212, 2012
Strong magnetic field effects on solid-liquid and particle-particle interactions during the processing of a conducting liquid containing non-conducting particles
The behavior of micrometer sized weak magnetic insulating particles migrating in a conductive liquid metal is of broad interest during strong magnetic field processing of materials. In the present paper we develop a numerical method to investigate the solid-liquid and particle-particle interactions by using a computational fluid dynamics (CFDs) modeling. By applying a strong magnetic field, e.g. 10 Tesla, the drag forces of a single spherical particle can be increased up to around 15% at a creeping flow limit. However magnetic field effects are reduced when the Reynolds number becomes higher. For two identical particles migrating along their centerline in a conductive liquid, both the drag forces and the magnetic interaction will be influenced. Such factors as interparticle distance, Reynolds number and magnetic flux density are investigated. Shielding effects are found from the leading particle IA hich will subsequently induce a hydrodynamic interaction between two particles. Strong magnetic fields however do not appear to have a significant influence on the shielding effects. In addition, the magnetic interaction forces of magnetic dipole-dipole interaction and induced magneto-hydrodynamic interaction are considered. It can be found that the induced magneto-hydrodynamic interaction force highly depends on the flow field and magnetic flux density. Therefore, the interaction between insulating particles can be controlled by applying a strong magnetic field and modifying the flow field. The present research provides a better understanding of the magnetic field induced interaction during liquid metal processing and a method of non-metallic particles manipulation for metal/ceramic based materials preparation may be proposed. (C) 2012 Elsevier Inc. All rights reserved.