感应加热时钢坯物理性能对温度场的影响

为研究钢坯各物理性能在感应加热过程中对温度场的影响,建立移动钢坯的电磁-传热耦合有限元模型,采用单因素分析法首先研究了某一特定物理量对钢坯温度场的影响,接着对比分析了物理性能相差较大的两种钢坯在多物理量均随温度变化时对温度场的影响。结果表明,相对磁导率对截面温度的影响主要由产生的较大感应电流及其较浅趋肤深度导致;在相对磁导率和热导率共同作用下,碳钢芯表温差略有缩小,不锈钢芯表温差略有升高;此外,结合实际加热过程--当多物理性能均随温度变化时,碳钢的电导率和比热容能减弱相对磁导率使加热过程中表面温度快速升高这一影响;最后的试验数据显示,在温度上升趋势一致的同时,理论计算较实际加热的结果高2.44%~6.97%。

Influence of billet physical properties on temperature field during induction heating

In order to study the influence of physical properties of billets on the temperature field during induction heating, a coupled finite element model of electromagnetic and heat transfer of moving billets was established, and the influence of a specific physical quantity on the temperature field of billets was studied by single factor analysis method. Then, the influence of the two billets with different physical properties on the temperature field is compared and analyzed. The results show that the influence of relative permeability on cross section temperature is mainly caused by the larger induced current and the shallower yield depth. Under the influence of relative permeability and thermal conductivity, the temperature difference between carbon steel core and surface decreases slightly, while that between stainless steel core and surface increases slightly. In addition, combined with the actual heating process, when multiple physical properties change with temperature, the conductivity and specific heat capacity of carbon steel attenuate the effect of the relative permeability on the rapid rise of surface temperature during heating. The final test data show that the theoretical calculation results are 2.44%-6.97% higher than the actual heating results while the trend of temperature rising is consistent.