刚塑性有限元解题法的改进及在轧制中的应用

本文对刚塑性有限元的初速度场及收敛性进行了专门的研究和改进。用于解决轧制工程问题,计算精度较高、CPU时间较少,它是一种可靠的理论分析方法。

Improvement on the Rigid-Plastic Finite Element Method and Its Application in Rolling Engineering

Rigid-plastic Finite Element Method ( RFEM ) is non-linear,so it is necessary to give a good initial velocity field and to ensure for evaluation. Ori K. I. proposed "function G" to determine the initial velocity field, but he didn' t make a through analysis. Newton-Raphson method is generally used in RFEM, but it has some drawbacks:1 ) it is possible to deverge during itterating;and 2 ) the step is difficult to determine, so that the calculating time is increased.In order to Overcome the drawbacks above mentioned,we advanced a new method-penality method of function G and carried on a detail analysis. As iteration method the Gill-Murrary mothod (improved Newton method) is used instead of Newton-Raphson method and the linear search is made by 0.618 method.The RFEM program is worked out for calculating parameters of plastic working processes. The calculating results obtained in studying roll-ing process coincide with the experimental data. The research shows clearly that the improved RFEM method is satisfactory for analysing plastic working problems.