连续铸造复合轧辊结晶器流场的数值模拟

Numerical Simulation of Fluid Flow in Continuous Casting Mould for Compound Roll

采用湍流两方程模型,对连续铸造复合轧辊组合结晶器内钢液的流场进行了数值模拟研究,分析了拉坯速度及浇注倾角等工艺参数对组合结晶器内钢液流场的影响.结果表明:钢液进入组合结晶器后分为三个流股,其中的两个流股对称地沿周向流动的同时向上反卷,在组合结晶器的上部形成两个对称的漩涡;另一个流股沿周向流动的同时向下流动,最终以几乎相等的流速流出结晶器.涡心位置随着拉坯速度的增大而下移,同一拉坯速度下,漩涡涡心在浇注倾角为60°左右时最低.在相同的拉坯速度下,随着浇注倾角的增大,钢液流股的穿透深度也随之增大.浇注倾角为15°时,钢液对辊芯的冲刷速度较大,而浇注倾角为90°时,钢液对辊芯的冲刷速度较小.

The fluid flow of molten steel in the continuous casting mould for compound roll has been simulated numerically using the κ-ε double equation model of turbulence to discuss the effects of casting speed and pouring angle on the fluid flow. The results showed that the molten steel enters into the mould assembly in three flows of which the two move upward peripherally at the same time to form symmetrically two eddies at the upper part of the mould, while the other one moves downward peripherally and, eventually, goes out of the mould at the speed about the same. And the eddy center moves downward with increasing casting speed. At the same casting speed, the eddy center is the lowest if the pouring angle is about 60° and the penetrating depth of molten steel flow increases with the increasing pouring angle. The scouring velocity of the molten steel against roll core is the highest and lower when the pouring angle is 15° and 90°, respectively.