多热源耦合下熔融炉数值模拟

Numerical Simulation of Melting Furnace with Multi-heat Source Coupling

等离子体炬耦合电极助熔加热的熔融炉可应用于危废处置领域。利用数值模拟的方法,将两相的二维计算域气相区和液相区分别建模,交界面用热流和温度迭代传递来简化,解耦合求解了区域内温度场和速度场分布。结果表明,只采用等离子炬加热浆池仅在浆池表面区域有影响,很难将热量传递到底部,大部分热量被烟气带走浪费,加热效率低。只采用底部电极加热可在浆池中心形成高温区,顶部形成料层区,减少了浆池内热量向气相区传递,提高了整体热效率。等离子体炬与电极同时加热时,温度分布接近与二者单独加热的叠加。因此利用电极助熔可以弥补等离子体炬单一热源加热的不足,对于工程应用具有重要意义。

The molten furnace heated by plasma torch coupled electrode can be used in the field of hazardous waste disposal. The gas phase and liquid phase in the two-dimensional computational domain are modeled by numerical simulation. The interface is simplified by heat flow and temperature transfer iteration. The temperature and velocity distributions in the two-dimensional computational domain are solved by decoupling. The results show that heating the molten pool by plasma torch only affects the surface area of the molten pool, and it is difficult to transfer the heat to the bottom. Most of the heat is taken away and wasted by flue gas, and the heating efficiency is low. Using only the bottom electrode heating can form a high temperature zone in the center of the molten pool, and form a wastel layer zone at the top, which reduces the heat transfer to the gas phase zone in the molten pool and improves the overall thermal efficiency. When the plasma torch and electrode are heated at the same time, the temperature distribution is close to superposition of the two separately heated. Therefore, electrode melting can make up for the shortage of single heat source heating plasma torch, which is of great significance for engineering application.