异径双辊薄带铸轧熔池中钢液流动特性

Numerical Study on Fluid Flow in the Molten Pool During Unequal Diameter Twin Roll Casting

采用有限差分和二维稳态层流模型，应用边界适体坐标（ＢＦＣ）技术对异径双辊薄带铸轧熔池中钢液的流动进行了数值仿真·分析了铸辊转速、液面宽度、浇注区宽度、浇注位置等操作和设计参数对流场的影响·计算结果表明钢液注入熔池后，在双辊相向转动的作用下，会引起强制对流并产生２个逆时针方向的回流区·通过对不同工况的分析指出浇钢时采取低压头、偏流浇注并维持一定的液面高度等操作有利于铸轧过程的稳定进行·

The finite difference method and 2 D steady laminar model were applied to the numerical simulation for the fluid flow inside the molten pool during unequal diameter twin roll strip cast rolling. The technique of boundary fitted coordinate systems (BFC) was employed to deal with the irregular molten pool geometry. The effects of roll rotation speed,molten pool level,filling area and filling position on the fluid flow were discussed to provide the guidelines for equipment design and operation parameters. The results show that the feeding flow dynamics generated by the twin rolls rotating in opposite direction each other produces two strong counter clockwise recirculating flows within the steel liquid pool. Numerical modelling by varying model parameters indicates that low feeding position,deviation feeding method and constant liquid level are the key factors to maintain a steady roll casting process.