通过流固耦合加热的轧辊温度场分析

针对目前镁合金板材轧制过程轧辊温度控制方式精度差，易造成板材的板形、板厚及裂纹等缺陷，采用流体循环流动传热的方式对轧辊进行温度控制，建立轧辊、流体传热过程的流固耦合模型，基于FLUENT软件对二者间的流固耦合传热过程进行数值模拟及试验验证。结果表明：用该方法加热轧辊时，辊身表面温度呈线性分布，边部与中间的温差范围为3～7℃，轧辊有效轧制区间占轧辊总长85%～100%左右，且流体温度与速度对其影响较小；在不同流体温度和流速下，轧辊表面温度均呈速率减小的趋势上升，流体温度升高及流速增大时，轧辊温升速率增大；得出在不同加热条件下，轧辊表面平均温度T与加热时间t的关系式；轧辊表面平均温度的试验与模拟值的最大相对误差为6.29%。该模型可正确预测轧辊表面的平均温度，作为镁合金板材轧制模型的一部分，利于轧制过程中轧辊的“等温”控制，实现“镁合金板材的等温轧制”控制。

Temperature Field Analysis of Roll Heated by Fluid-solid Coupled Heat Transfer

At present, the roll temperature control method in the magnesium alloy rolling process is inaccurate, which has a serious influence on the shape, crack of the sheet. The temperature control of the roll is carried out by means of fluid circulation, using FLUENT software to simulate the fluid-solid coupled heat transfer and verifying by experimental results. The results show that the roll heated by this method the surface temperature distribution is linearly distributed, and the temperature difference between the edge and the centre is in the range of 3-7℃, the effective roll interval accounts for 85%-100% of the total length of the roll, and the fluid temperature and velocity have little effect on it. At different fluid temperatures and velocities, the roll temperature increases with the decrease of decreasing rate. The relationship between the roll surface temperature and the time is obtained under different heating conditions in this study. The simulated values of the average roll surface temperature agree well with the experimental values, the maximum relative error is 6.29%, which shows that the model can predict the average temperature of roll surface accurately, and as part of the magnesium alloy plate rolling model, it is conducive to the isothermal control of the roll in the rolling process and realizes isothermal rolling control of magnesium alloy plate.