Study And Software Design Of Several Problems For Structural Topology Optimization Based On SiPESC

After years of intensive investigation by domestic and foreign scholars, the structural topology optimization theory and method has gradually matured, and this technique has been one of the powerful tools for engineering optimization design. Therefore, structural topology optimization modules have been successively integrated into various commercial CAE software in recent years. However, many kinds of commercial software restrict the application of the latest research achievements to the practical engineering in time because of their own technical privacy and time lag of development. Recently, a structural topology optimization subsystem named SiPESC.TOPO has been developed by the R&D team of SiPESC at DLUT, which has good open-ability and extendibility, and can supports collaborative development involving multi-users or multi-organizations. SiPESC.TOPO can satisfy the demand of user for theoretical research, meanwhile is suitable for engineering application.In this paper, investigation is paid to the theory and numerical algorithm of several structural topology optimization problems, including the variable connection algorithm with manufacturing constraints and engineering requirements, the structural topology optimization problems with the buckling response and stress constraints. Furthermore, based on the structural topology optimization subsystem, this paper designs the corresponding plug-ins and improvesthe function of software system. Main contributions of the paper are as follows.A new topology optimization formulation with variable connection concept is proposed, and the formula for sensitivity analysis is presented. With the new topology optimization formulation, the manufacturing constraints and engineering requirements are solved, therefore the optimization design variables are reduced and the computation scale is reduced. Based on the open design framework of SiPESC.TOPO, this paper proposes the design method of "algorithm+pattern", including the factory pattern, and the open variable connection algorithm framework, and then it realizes the dynamic selection and replacement of numerical algorithms. In consideration of the importance of buckling failure in practical engineering, the model of continuum structural topology optimization with linear buckling response is presented based on the former researches for the buckling optimization by domestic and foreign scholars. In addition, the sensitivity analysis formulas for linear buckling eigenvalue is deduced in detail and then the structural topology optimization module with linear buckling response is implemented in SiPESC.TOPO. Furthermore, the structural topology optimization with stress constraints is investigated and the attention is paid to the singular solution phenomenon and large-scale computational problems. Main work is to deduce the sensitivity formula based on the rule of Mises and to realize the software module in SiPESC.TOPO.Numerical examples are presented to verify the accuracy and applicability of the theory and numerical algorithms in this paper, for the variable connection algorithm and the topology optimization module with linear buckling response and stress constraints. It is also show that software design methods and framework of SiPESC.TOPO takes advantages over other software in software open ability and extensibility.