Design And Implementation Of Component Mode Synthesis Based On SiPESC Platform

With the increasing scale of engineering problems, the role of the finite element numerical software is also increasingly important, but for various reasons, Chinese finite element numerical software market is almost monopolized by foreign commercial software. In this context, Dalian University of Technology has developed a new generation finite element numerical software platform—SiPESC, it is based on "platform+plug-in ", which is a new software architecture, making the SiPESC software platform has excellent flexibility, scalability and ease of maintenance.Modal analysis is the basis of the dynamic analysis and dynamic design. As the engineering structures has become increasingly large and more complex, general modal analysis methods and even the general method for solving large-scale modal analysis is unable to complete the calculation, computer resources and computation time limitations restrict the ability of engineers to solve these large scale problems. Some engineering structures are analyzed by different departments or regional organizations, therefore, when in the process of analysis and design, only components, not the overall structure,can be calculated or tested, on the other hand, as for some structure which is not large, but more complex, it is difficult to establish its numerical model, while the experiment test can be easily processed for its dynamic characteristics. These engineering requirements arise the question of how to assess the dynamic characteristics of the overall system by component dynamic characteristics. The above-mentioned problems can be effectively addressed by the dynamic substructure method., which can also effectively combine the two means of experiments and calculations. So the dynamic substructure method has become one of the most effective way to analyze large and complex structural systems.As a dynamic substructure method, Modal synthesis method is most widely used, therefore it is a key task to integrate the method into the SiPESC.Based on SiPESC platform, this paper has implement four kinds of modal synthesis method, which are Craig-Bampton method (fixed-interface modal synthesis method), multilayer Craig-Bampton method, free-interface modal synthesis method(Bi-compatible method), and mixed-interface modal synthesis method(an improved bi-compatible method). This paper presents an efficient searching algorithm for substructure interface points. Craig-Bampton in this paper takes into account the rotation and translation of the substructure, multi-layer Craig-Bampton method can consider a variety form of multi-layer substructure. Because SiPESC employs a new software architecture and program design ideas, Design and implementation of program on the SiPESC platform is very convenient.By constructing numerical example, and compared with the calculation results of Ansys and MSC.Nastran, proving a good precision of the method in this paper.