勾配磁場による水‐磁性微粒子分散流れからの磁性微粒子の分離

Abstract

First, experiments have been conducted on separation of ferromagnetic particles from water-ferromagnetic particles dispersion flow by a magnetic field gradient. The test section, in which the magnetic field gradient is applied, is 0.05 m in height and 0.5 m in length. The experimental conditions are 0.1 m/s for inlet velocity, 0.0001 for inlet particles volume fraction and 0.0 T to 0.5 T for magnetic field (in the magnetic pole piece). The ferromagnetic particles are cobalt particles with an average diameter (at the test section inlet) of 8.4 μm. Secondly, numerical calculations have been performed in simulating the experimental test section and experimental conditions. In the calculations, increase in the particle diameter by the aggregation of magnetized particles has been considered in order to get better agreement between calculated and experimental results. It has become clear from experimental results that the larger the magnetic field becomes the smaller the particles volume fraction at the test section exit becomes and the volume fraction at the exit is nearly zero for a magnetic field of 0.5 T. It has also become clear from calculation results that the larger the magnetic field becomes the larger the particles volume fraction at the bottom of test section (meaning the particles accumulation in this region) and the smaller the volume fraction at the test section exit becomes.