【作者】 李阳；

【导师】 李德群；

【作者基本信息】 华中科技大学 ， 材料加工工程， 2008， 博士

【摘要】 目前塑料注射成形CAE软件在使用过程中存在着对专业知识依赖过多,智能化程度不高等缺点,极大地制约了注射成形CAE软件的推广和应用。本文围绕着注射成形CAE软件的应用和智能化开展了深入而系统的研究。通过分析注射成形CAE系统中主要使用的三种分析模型的优缺点及其应用范围,指出了根据零件类型选择合理的分析模型是获得正确分析结果的关键因素。在工艺方案分析的前置处理阶段,在双面模型上建立了基于流动平衡的注射成形浇口优化模型,给出了流动平衡的判定方法,采用简化条件推导出等效流长模型,成功地将有限元网格几何模型拓展成带权值的无向图,使得流长求解问题转变为无向图的最短路径问题,并利用最短路径法求解。建立了约束域的遗传与爬山混合优化算法,能够在制品空间中搜索最佳浇口节点。在后置处理阶段,针对CAE中评价标准不统一、随意性强的问题,系统地总结了基于CAE场量分析数据的注射制品质量缺陷评价方法,给出相应的自动评价算法,并且应用模糊综合评价方法建立了基于CAE计算结果的注射成形方案综合评价模型,可以有效地指导工艺人员对方案的评价。对于评价等级达不到要求的工艺方案,本文建立了相关的模糊推理系统,该系统包括了输入输出变量的模糊化、规则的模糊表达、推理方式的确定、冲突的消解与合成等功能。更多还原

【Abstract】 There are some disadvantages in the application of CAE software for plastic injection molding such as redundantly depending on the experience and knowledge of injection molding and lowly intelligent ability. These disadvantages greatly limit the application of CAE software for ijection molding. In respect to this, the application and intelligentization of CAE software for injection molding has been systemically studied in this paper.The advantages and disadvantages of three kinds of analysis models which are mainly used in CAE software for injection molding have been discussed. And the suited applied areas of each model have been studied. The key factor to get the accurate results which is to choose an appropriate kind of analysis model has also been pointed out.In the pre-processing stage, the optimized model which is used to optimize the gate location according to the cavity balance has been constructed on the fusion geometry model. The method to evaluate the melt flow balance is put forward. The finite element mesh geometry model has been successfully transformed to the weighted undirected graph through the model of equivalent flow length which is derived on some simplified conditions. Therefore, the problem of calculating the flow length changes to calculate the shortest path of the undirected graph and the flow length could be got by the shortest path method. A new method combining the Generic Algorithm and Hill-Climbing Algorithm has been used to search the best gate node.In the post-processing stage, the methods have been summarized which are used to evaluate the quality of injection molding parts based on the data calculated by the injection molding software, and the automatic algorithm of the evaluation is also constructed according to the methods mentioned above. Using the theory of Fuzzy Comprehensive Evaluation, the comprehensive evaluation model based on the analysis results of CAE software has been structured and it could help engineers to evaluate the processing parameter setting.A fuzzy inference system has been developed to optimize the processing parameter which does not meet the request. The system includes fussy of the input and output data, fussy of the rule, confirming inference rules, and eliminating and compound of the conflict.更多还原