VTHS-EMBr宽板坯结晶器内电磁场特性及控流行为数值模拟研究

Numerical Simulation Study on Electromagnetic Field Characteristics and Flow Control Behavior in VTHS-EMBr Wide Slab Mold

摘要: 宽板坯连铸的核心难题之一，便是结晶器内钢液流动的精准调控——这关系到铸坯的最终质量。针对1200 mm、1400 mm和1600 mm三种宽度的结晶器，搭建了恒定通钢量下的数值模拟模型，重点探究新型立式与水平磁极组合装置(VTHS-EMBr)的作用效果。模拟中固定水平磁极电流为350 A，通过改变立式磁极的电流强度(100 A、300 A、500 A)和频率(1~9 Hz)，研究钢液流动变化。模拟结果显示：随着结晶器宽度从1200 mm增至1600 mm，加入相同立式磁极电流IV = 100 A时结晶器内部最大磁感应强度均为0.085 T，内部磁场变化不随宽度的增加而变化。频率从1 Hz升至9 Hz时，感应电流从2000 J (A/m²)提升至42,000 J (A/m²)，感应电流的强度与作用范围随着频率的增加而增大。无磁极工况下随着结晶器从1200 mm增加至1600mm钢液表面流动速度从0.33 m/s降至0.25 m/s，在施加VTHS-EMBr电磁制动后，1200 mm宽度下结晶器内钢液表面流动速度降至0.27 m/s，1600 mm宽度下结晶器内钢液表面流动速度升至0.30 m/s。本文研究为宽板坯连铸中多维度电磁制动技术提供了理论支撑。

Abstract: One of the core challenges in wide slab continuous casting is the precise control of molten steel flow in the mold, which is crucial for the final quality of the slab. A numerical simulation model under constant steel throughput was established for molds with three widths: 1200 mm, 1400 mm, and 1600 mm, focusing on investigating the effect of a new vertical and horizontal magnetic pole combination device (VTHS-EMBr). In the simulation, the horizontal magnetic pole current was fixed at 350 A, and the changes in molten steel flow were studied by varying the current intensity (100 A, 300 A, 500 A) and frequency (1~9 Hz) of the vertical magnetic poles. The simulation results show that as the mold width increases from 1200 mm to 1600 mm, the maximum magnetic induction intensity inside the mold is 0.085 T when the same vertical magnetic pole current IV = 100 A is applied, and the internal magnetic field change does not vary with the increase in width. When the frequency increases from 1 Hz to 9 Hz, the induced current increases from 2000 J (A/m²) to 42,000 J (A/m²), and the intensity and action range of the induced current increase with the increase in frequency. Under the condition without magnetic poles, as the mold width increases from 1200 mm to 1600 mm, the molten steel surface flow velocity decreases from 0.33 m/s to 0.25 m/s. After applying VTHS-EMBr electromagnetic braking, the molten steel surface flow velocity in the mold decreases to 0.27 m/s for the 1200 mm width and increases to 0.30 m/s for the 1600 mm width.