粘弹性模型的参数换算研究

Study on the characteristic parameters conversion of viscoelastic constitutive models

通过对常见的粘弹性材料模型的本构方程分析,将其变换为以应变量和应变率为自变量来表示的应力函数型本构关系;同时分析了不同本构方程间材料特性参数换算的问题,并提出了根据最小偏差平方和进行参数换算的方法和步骤;最后给出了计算实例,实现了给定材料在不同模型和不同受力条件下的材料的特性参数换算,并分析了由于换算带来的计算误差.

Based on the general expressions of viscoelastic constitutive models, the constitutive relations of viscoelastic materials are transformed into stress function constitutive relations which are expressed by strain rate and strain. The transform problem of the material parameters between the different constitu- tive models is solved by the method of minimum sum of squared deviations, and the definite method and procedure are supplied. In the case studied, the given material parameters transform is demonstrated un- der different constitutive models and different stress states, and the calculation errors are analyzed.