An Evaluation Index for Estimating Defeaturing-Induced Impacts on Finite Element Analysis

Defeaturing is a popular CAD/CAE simplification technique. However, defeaturing inevitably leads to errors that can not be effectively evaluated yet during a FE (Finite Element) analysis. In this paper, a novel evaluation index based on the reciprocal theorem is proposed to effectively and efficiently estimate defeaturing-induced impacts on FE analysis. Instead of using the difference of strain energy, the proposed evaluation index uses the difference of work to quantify the defeaturing-induced impacts on FE analysis so that it is not only effective but also can be efficiently calculated. In order for an efficient calculation of the evaluation index, a practical evaluation index is further derived from the proposed theoretical index, and its calculation method is given. The practical evaluation index has been applied to FE static computation of linear elastic structures. Therefore, we are able to adapt the simplification of a model according to a desired accuracy of the analysis results.