多道次中厚板热轧过程的综合数值解析法模拟

Simulation of Multi-pass Plate Hot Rolling by a Mixed Numerical and Analytic Method

采用微分方程的解析解法和数值解法相结合的思路建立了中厚板热轧过程温度场、变形场和轧制力的综合求解模型.在该模型中,考虑到轧件厚度方向的温度梯度远大于沿宽度和长度方向的温度梯度,因而将热传导方程简化为一维微分方程,基于拉格朗日坐标建立了温度场的级数解法.针对中厚板轧制的速度场特点设定了速度场函数,基于欧拉坐标架建立了应变速率和应变的数值解法,从而解决了多道次轧制过程的温度场与变形场连续计算问题.利用该模型模拟了中厚板12道次热轧的成形过程,给出了轧件温度随时间的连续变化曲线以及各道次的轧制力、应变和应变速率的分布和大小.模拟结果与工业现场实测数据吻合较好.

A combined analytic and numerical method for predicting the temperature, deformation and rolling pressure for plate hot rolling was established. Considering that the temperature gradient through thickness is much higher than that through width and length of plate, in this model, the governing equation of heat transfer was simplified as a one dimensional differential equation, and the series function solution for temperature is established in Lagrangian coordinate setting. According to the characteristics of plate rolling, the flowing velocity function of material is assumed, upon that the numerical solutions of strain rate and strain are established in Eulerian coordinate setting. The model is able to carry out the continuous computations of temperature and deformation for multi-pass rolling. As an application, a 12-pass hot rolling of steel plate was simulated, and the temperature changes vs. time as well as the rolling force and the distributions of strain and strain rate at different passes were demonstrated. The simulated results show a satisfactory coincidence with the industrial measured data