超薄大断面异型坯结晶器非对称流场和温度场的优化

建立0.7∶1的水力学试验模型优化水口结构来改善超薄大断面异型坯结晶器流场,并对实际生产工况下结晶器及其二冷段内钢液的三维流场和温度场进行了数值模拟。结果表明,现有直通型水口结晶器内流场分布极不对称,结晶器内各位置响应时间相差较大,造成结晶器内温度、成分等分布不均匀。优化后的三侧孔一底孔型水口浇铸有效地解决了结晶器各位置响应时间较长且不一致的问题,有效改善了单点直通型水口浇注时的严重不对称流场,浇注侧和非浇注侧的温度差异明显缩小,沿拉坯方向的温度变化也较为合理,有利于良好凝固坯壳的形成,为实际生产提供了指导。

Optimization of asymmetric flow field and temperature field of ultra-thin and large section beam blank mould

A 0.7∶1 hydraulic test model was established to optimize the nozzle structure to improve the flow field of ultra-thin large section blank, and the three-dimensional flow field and temperature field of molten steel in the mold and its secondary cooling section were numerically simulated under actual production conditions. It was showed that the flow field distribution in the existing through nozzle mould was extremely asymmetric and the response time of each position of the mould was quite different, resulting in the uneven distribution of temperature and composition in the mold. The optimized three-side hole and one bottom-hole nozzle effectively solves the problem of long and inconsistent response time at different positions of the mould and improves the serious asymmetric flow field during single-point straight-through nozzle pouring. The temperature difference between the pouring side and the non pouring side is significantly reduced, and the temperature change along the drawing direction is also more reasonable, which is conducive to the formation of a good solidified shell. This process provides guidance for actual production.