基于Matlab的中厚板轧后冷却过程温度场数值研究

基于Matlab数值计算，对中厚板轧后冷却问题进行了研究，得到了中厚板随时间变化的温度场分布，分析了钢板厚度、终轧温度、冷却水温度、平均水流密度、钢板含碳量和冷却方式对钢板表面和芯部温度、终冷温度的影响。结果表明，钢板芯部与表面的温差，在空冷阶段先增大后趋于平稳；在层流冷却阶段随着冷却时间的增加不断增大；在返红阶段在较低的范围内趋于平稳。在相同的冷却时刻，随着钢板厚度的增大，钢板表面温度、芯部温度以及芯部与表面的温差均增大；随着终轧温度的降低和平均水流密度的增大，钢板表面和芯部终冷温度均降低。随着钢板含碳量的增加，其表面温度并不总是降低。与单水冷过程相比，间歇式冷却使钢板芯部与表面的温差更小，钢板温度均匀性更好，其对应的热应力也较小。同时，得到了终冷温度与钢板厚度、终轧温度、冷却水温度和平均水流密度的拟合关系式，结果表明钢板终轧温度对钢板终冷温度的影响最为显著，其次是钢板厚度和平均水流密度，冷却水温度对其影响较小。

Numerical Study on Temperature Field of Cooling Process after Plate Rolling Based on Matlab

Based on numerical calculation with Matlab, the study on cooling process after plate rolling was car ried out, and the temperature field distribution of the plate varying with the time was obtained. The effects of the plate thickness, final roiling temperature, cooling water temperature, average flow rate of the cooling wa ter, carbon content of the plate and cooling method on the plate surface and central temperatures as well as fi nal cooling temperature were discussed. The results show that during the air cooling stage, the temperature difference between the plate center and surface increases first, and then tends to be stable. During the laminar cooling stage, this temperature difference increases with the increase in cooling time. During the self-tempering stage, this temperature difference tends to be stable at a low value. For the same cooling time, the plate sur- face and central temperatures as well as their temperature difference increase. With the decrease in rolling tem perature and the increase in average flow rate of the cooling water, the plate surface and center temperatures decrease. With the increase in carbon content of the plate, its surface temperature is not always decreased. Compared with the single water cooling process, the temperature difference between the plate center and sur- face based on intermittent cooling is lower. In this case, the temperature uniformity of the plate is better, and the corresponding thermal stress is lower. The fitting equation of the final cooling temperature with respect to plate thickness, final rolling temperature, cooling water temperature and average flow rate of the cooling water is also obtained. It is shown that the effect of the final roiling temperature on the final cooling temperature is more obvious, the effects of the plate thickness and average flow rate of the cooling water on the final cooling temperature are secondary, but the effect of the cooling water temperature on the final cooling temperature is little.