汽车车身CAE分析中焊点模型的易用性

白车身通常有数千焊点,不同的焊点模拟方法对于CAE分析精度有重要影响.白车身CAE开发中焊点模拟有3种主要方式：点对点刚性单元（如RBE2,CROD,CBEAM等）、剪弹性梁单元（如CWELD,CFAST）和ACM2类型的六面体单元加RBE3单元连接.讨论了3种类型焊点模拟方法在工程中的应用,通过模态对比分析和易用性总结得出：点对点刚性使用简单,但分析精度较低；剪弹性梁单元易用性复杂,分析精度最高；ACM2单元易用性和分析精度均介于二者之间.为白车身CAE分析中焊点模拟方式的选择提供参考.

Modeling Facility of Welding Spot Joints in Automotive Body in White for CAE Analysis

Normally, there are thousands of welding spots in the body in white （BIW）, the performance of the weld models is one of the most effective factors which affect the accuracy of the CAE analysis. Three different types of welding spot joints models are developed in CAE analysis of BIW. The first type is the rigid elements, such as RBE2, CROD, CBEAM etc. The second type is CWELD and CFAST, which is a kind of shearing-elastic beam elements. The third type is ACM2 （Area Contact Model2）, the model is developed using a brick element and connected to the joints surfaces via RBE3 elements. This article first outlines the application of the three kinds of weld models in the CAE analysis of the BIW. It is turned out that the rigid element is easy to use with low accuracy, the shearing-elastic beam element is more complicated with high accuracy, and the ACM2 model is the model with intermediary performance, which provided the reference for selecting the model of welding spot in CAE analysis of BIW.