Numerical analysis for clustering of carbon particles in the natural and magnetic convection flow field of air

Xian Wang, Hiroyuki Hirano, Toshio Tagawa, Hiroyuki Ozoe, Qiuwang Wang

In the present work, the behavior of carbon particles in natural and magnetizing convection of air was numerically studied. 1000 carbon particles were released randomly in a vertical cylinder whose height is equal to its radius. The cylindrical encosure was heated from below and cooled from above. A coil with electric current was set coaxially with the enclosure and at the same level of the enclosure bottom to produce a magnetic field. The results show that when the particle diameter is less than 1$\mu$m, the Brownian motion is obvious and must be taken into consideration. Small-sized particle (d<1$\mu$m) receives more effect from flow field, so that the natural convection depress the Brownian motion of the small-sized particles. Large-sized particle (d=5$\mu$m) receives more effect from gravitational and magnetic fields and can be levitated in the magnetic field. Large-sized particle is easier to cluster than small-sized one.
Symposium on New Magneto-Science 2003

Symposium on New Magneto-Science 2003, Proceedings of the 7th Meeting, pp.138-143