Numerical Simulation of Synthesis Silicon Carbide by Carbothermal Reduction
1. Shaanxi Railway Institute, Weinan 714000, China;
2. School of Material Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, China;
3. State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China
Abstract In order to reveal the mechanism of energy and material diffusion in the process of silicon carbide synthesis so as to lay the theoretical foundation to improve the yield and quality of silicon carbide, the numerical simulation method was used to simulate the temperature field, pressure field and gas flow in the process of silicon carbide synthesis. The results showed that with the increase of the synthesis time, the heat in the furnace was radiated outward and the gas in the synthesis furnace exhibited three-dimensional multi-directional flow characteristic. When the reaction progressed to 24 h, the gas flow rate reached the maximum. At this moment, due to the poor ventilation at the bottom of the furnace, the pressure at this point was higher than the remaining position and the maximum was 1.525×101 kPa. At this time, a small amount of wood chips can be added to increase the permeability of the furnace to improve the pressure to avoid the spouting of furnace by the over high pressure. The simulation results have been verified by the production practice.
