Increasing Efficiency of the Design Process with an Isogeometric Analysis Plugin for Siemens NX by Analyzing the CAD Model Directly

The bottleneck for today’s integrated CAD and CAE tools or for the design-through-analysis process in general is the fact that for each product at least two different geometry representations are used. On the one hand side there is the CAD model and on the other hand side there is the finite element mesh, both representing the same object. The conversion between CAD model and FE model are named meshing and CAD reparameterization, respectively. These operations are error prone, time consuming and cannot fully be automatized. The current approach in industry to close the gap between CAD and CAE is to use more sophisticated and highly specialized tools. In consequence taking benefits out of new algorithms and tools becomes harder and harder. A completely new approach to overcome the problem of different geometric models is to use one model for both, which means to use the CAD model directly for the analysis. The corresponding approach is called Analysis in Computer Aided Design (AiCAD) [2]. The AiCAD concept is based on isogeometric B-Rep analysis (IBRA) [2], a new finite element technique. IBRA uses CAD models, especially NURBS based B-Rep models, instead of finite element meshes for approximating solution fields. The AiCAD concept is realized in the integrated CAD/CAE/CAM software Siemens NX 9.0 [3] with a plugin, which extends the CAD tool by the missing analysis functionalities. For the isogeometric B-Rep analysis itself the software CARAT++, developed at the Chair of Structural Analysis of the Technische Universität München, is used. In the following the basic steps necessary for the AiCAD concept within Siemens NX 9.0 are briefly summarized.