【作者】 金雪燕；

【导师】 隋允康；

【作者基本信息】 北京工业大学 ， 固体力学， 2003， 硕士

【摘要】 在给定了板壳的材料常数、板壳结构的边界形状和边界条件的前提下，确定表征板壳厚度的设计变量，在满足约束条件下实现结构重量最小：1.对于尺寸和应力约束的问题，使用满应力方法求解。在每一步迭代过程建立优化模型之前，采用射线步技术，调整了结构的性态，保证了收敛的稳定性。2.对于尺寸、应力和位移约束的问题，将应力约束化为动态下限，用单位虚荷载方法将位移约束近似显式化，构造优化问题的数学规划模型，将其对偶规划处理为二次规划问题，采用LEMKE算法进行求解，得到满足尺寸、应力和位移约束条件的截面最优解。在MSC/NASTRAN基础上，利用MSC/PATRAN提供的PCL语言，对板壳结构的截面优化的优化模块进行了二次开发。将建立优化模型的菜单融合到PATRAN界面，用户可以通过人机界面的交互功能确定设计变量、约束条件及目标函数三要素，实现程序的可视化。 多个算例验证了程序具有合理性、精确性和收敛速度快等特点。更多还原

【Abstract】 On the premise of a given set of material parameter, structural boundary shape and condition, design variables-thickness of plate and shell, is designed to minimize the structural weight subjected to the constraint conditions. 1.For the problem with size and stress constraints, full stress design method is used to solve the sectional optimization of plate and shell structures. Before the optimization modeling, the scaling step technique is used to adjust the structural behavior, and the stability of computational convergence is ensured.2.For the problem with size, stress and displacement constraints, the stress constraint is transformed into movable lower bounds of sizes, the displacement constraint is transformed into an approximate function which explicitly includes design variables by using Mohr integral theory. A mathematical programming model of the optimization problem is set up. The dual programming of the model is approached into a quadratic programming model. Finally, the Lemke algorithm is used to get the design result which satisfies the size, stress and displacement constraints.Based on MSC/NASTRAN software, by using of PCL language (PATRAN Command Language), new software of optimum design module was secondly developed for sectional optimization of plate and shell structures. Visualization is realized by setting the menu into PATRAN. Users can define design variables, constraint conditions and objective function by the iterative function of computer interface.Some numerical examples of optimum design verified the credibility, validity and speed convergence of the program.更多还原