有限元法求解瞬态温度场时的振荡问题

Oscillation Problem During Solving for Transient Temperature Field Using FEM

针对有限元方法求解瞬态温度场时产生的时间和空间上解的振荡问题,分析了温度振荡现象产生的原因。以中厚板生产过程为背景,通过采用集中热容矩阵的向后差分格式的方法解决了振荡问题。利用该方法得到的中厚板生产过程中瞬态温度场的计算结果和实测数据进行了验证比较,结果吻合良好。

The problem of time and spatial numerical oscillation is found while transient temperature field is computed by finite element method. By analyzing the reason of the numerical oscillation phenomenon and computing the temperature field in plate rolling process, it is found that numerical oscillation can be restrained effectively when the heat capacity matrix is lumped by using backward difference scheme. The highly precise results are obtained by computing the temperature field in plate rolling process when the above method is adopted.