热顶电磁成型系统磁场的实验与数值模拟

根据电磁场理论,建立了热顶-电磁连铸成型系统的物理和数学模型,用小线圈法实测了不同电源功率时系统内的磁场强度,用有限元软件数值模拟了感应线圈高度、结晶器高度、热顶结构等对成型系统内磁感应强度和分布的影响,结果表明:1)降低结晶器高度使系统内磁感应强度增强,但不十分明显;2)感应线圈的高度对系统内磁场影响显著,采用20mm线圈较40mm线圈的磁感应强度提高约85%;3)有载时的模拟结果显示,系统内的磁场呈现更明显的趋肤效应;热顶结构对磁场的强度和分布规律无明显的影响.研究结果表明热顶电磁连铸法将有利于提高电源效率和稳定液柱高度,改善铸坯的内外部质量.

Experimental and numerical simulation of the magnetic field in the Hot-top electromagnetic continuous casting system

Based on the theory of an electromagnetic field, the physical and mathematic models of a hot - top e-lectromagnetic continuous casting system have been constructed. The little coil method was used to measure the magnetic field of the shaping system under different powers. Finite element software has been used to numerically simulate the influence on magnetic flux density and the distribution in the mold in terms of the height of the inductor and the mold as well as the structure of the hot - top. The results have shown that: 1) reducing the height of the mold could enhance magnetic flux density in the system, but it wasnt obvious; 2) the height of the inductor had a measurable effect on the magnetism of the system ( using the inductor with a height of 20mm could increase the magnetic flux density 85 percent over using the inductor with 40mm in height); 3) the numerical simulation results with the load showed that the skin effect of the magnetic field was becoming obvious. Hot - top had no obvious influence on the magnetic flux density and distributing rule. It showed hot - top electromagnetic continuous casting technology would be favorable to improve the efficiency of the power and to stabilize the height of the liquid column, and could improve the quality of the interior and surface of the ingot.