Simulation of Bidirectional Coupling Effect of the Thermal Conductivity and Density of Electromagnetic Levitated Silicon Droplets on the Flow and Thermal Fields

During electromagnetic levitation, the thermal conductivity and density of droplets will change with temperature, which will affect the droplet flow field and thermal field. In this paper, the effect of bidirectional coupling of the thermal conductivity and density of silicon droplets on the flow field and temperature field is simulated. The results indicate that (1) The equilibrium levitation position of a droplet under bidirectional coupling circumstances is higher than that under unidirectional coupling circumstances, and the calculated results under the bidirectional coupling condition are more consistent with the experimental results. The most stable levitation state of the droplet is found to be at 390 A under bidirectional coupling circumstances, in contract to that at 410 A under unidirectional coupling circumstances. (2) The bidirectional coupling of thermal conductivity and density has little effect on the flow field, and the maximum velocity of the droplet under the bidirectional coupling condition is slightly smaller. (3) With bidirectional coupling, the thermal conductivity gradually decreases with the increase of temperature, and the upward trend of the droplet’s temperature under this condition is more evident than that with a constant thermal conductivity in the unidirectional model. The increasing trend of temperature in the former case is 17.4 K higher than that in the latter with the levitation current increasing from 360 to 560 A.