电磁软接触连铸圆坯结晶器传热分析

针对电磁软接触连铸过程,建立了结晶器三维电磁场及温度场模型,研究了电流、电源频率、铸坯与结晶器间热流密度以及绝缘材料导热性能对温度场的影响.结果表明,在高频电磁场作用下结晶器壁温度相比传统连铸结晶器有所提高.当前计算条件下,频率和电流增大,结晶器壁峰值温度随之升高.热流密度的大小直接决定着结晶器壁的温度分布,热流越大,温度沿高度方向的不均匀性越明显,沿结晶器周向,由于材料不连续引起的温度梯度也越大.绝缘填缝材料的导热性能对结晶器壁温度分布有较大影响,导热性能差的绝缘材料使温度沿高度方向出现两个峰值,分别对应于切缝的两端,加大了铜壁的温度梯度.

Heat Transfer Analysis of Round Billet Mold During Electromagnetic Soft-Contacting Continuous Casting

Aiming at the process of electromagnetic soft-contacting continuous casting,a three-dimensional finite element model of electromagnetic field and temperature field was developed to investigate the influences of power frequency,current intensity,heat flux between casting billet and copper mould and heat conductivity of thermal insulation material on the temperature field.The results showed that in comparison to the conventional continuous casting mold,the wall temperature of copper mold increases under the action of electromagnetic field,and the higher the current intensity and frequency,the higher the peak value of mold wall temperature.The magnitude of heat flux determines directly the temperature distribution of copper mould.The bigger the heat flux,the clearer the heterogeneity of temperature along the mold axis,and the circumferential temperature gradient in mold increases because of material's uncontinuity.The conductivity of filled insulation affects greatly the temperature distribution on the wall of copper mould.When the heat conduction coefficient of insulation is lower,there are two axial temperature peak values which correspond to the two ends of a seam on the wall of copper mould,and they will increase axial temperature gradient of copper mould.