【作者】 叶金蕊；

【导师】 张博明；

【作者基本信息】 哈尔滨工业大学 ， 工程力学， 2009， 博士

【摘要】 复合材料以其轻质、高强的优越特性广泛应用于航空航天等领域,但昂贵的制造成本是扩大其应用的主要障碍,如何减轻结构重量的同时降低成本、提高复合材料的性价比成为目前复合材料研究领域的核心问题之一。复合材料结构设计和制造过程中,通过大面积整体化成形技术,将几十甚至上百个零件减少到一个或几个零件,减少分段、减少对接、节省装配时间,可大幅度地减轻结构重量同时降低结构成本。复合材料加筋壁板是飞机典型的整体化结构,早期设计阶段建立科学的制造成本估算方法,有助于加筋壁板结构性能与成本权衡,不仅可作为材料选择的依据,还可用于工艺优选,实现低成本化结构的最优设计。然而,国内外有关复合材料加筋壁板设计的研究大多针对加筋几何形状能否满足结构性能要求,以壁板各组成部分铺层为研究对进行整体化结构优化设计,很少研究者考虑以成本为目标函数进行结构设计。本文基于整体化成形工艺,针对压剪组合应力作用下的复合材料加筋壁板结构,面向制造成本,以壁板结构稳定性要求和可制造性约束为前提条件,开展成本-重量权衡的结构设计研究:1.针对复合材料加筋壁板结构,建立了基于整体化成形工艺的制造工艺时间估算模型,并结合一阶反应动力学和幂定律原理给出模型参数、估算变量的确定方法。应用本文建立的工艺时间估算模型对共固化成形波纹形腹板壁板结构的铺层工序进行研究,模型估算值与实验值基本吻合,验证了模型的有效性,为复合材料加筋壁板结构制造成本估算奠定了理论基础。2.针对复合材料加筋壁板结构,建立整体化结构制造成本估算模型,提出了与制造工艺相关的材料成本、人工成本、设备成本和模具成本的估算方法。以共固化、二次胶接和胶接共固化三种整体化工艺成形复合材料蒙皮T形加壁板为例,应用制造成本估算模型进行研究,理论分析和实验结果吻合,验证了模型的适用性。所得结论有助于指导复合材料加筋壁板结构早期制造工艺优选,为面向制造成本的结构设计提供依据。3.分析复合材料加筋壁板结构复杂性对制造时间的影响,提出适合7种典型加筋壁板的结构的复杂效应表达式,并根据具体工程实例给出在结构复杂性影响下,制造工艺时间估算方程中工艺参数的修正方法。基于复合材料加筋壁板的固化特点,建立科学的固化时间估算方法,并结合国外对合模速率的研究,提出了合模工艺时间估算方法,有利于提高复合材料加筋壁板结构成本估算的准确性,为整体化结构面向结构复杂性设计提供依据。4.详细分析了压剪组合应力作用下复合材料加筋壁板影响结构设计的前提条件稳定性要求和可制造性约束,分别给出整体壁板结构屈曲、蒙皮湾处屈曲和加强筋柱状屈曲的解析表达式,与设计变量和结构几何尺寸紧密结合,研究了加强筋发生局部屈曲破坏的判别方法,与ANSYS非线性有限元分析结果进行对比,所得结论吻合较好,验证屈曲解析分析法的适用性,为建立飞机复合材料低成本结构设计与制造之间的有机衔接进行探索。5.以制造成本为目标函数,满足压剪载荷下结构稳定性要求和可制造性约束,提出一种基于成本-重量平衡的设计方法,并对相关流程进行详细研究。建立了7种横截面形状的加筋壁板成形工序表,并分别讨论了三种整体化成形方法的差异。基于典型加筋壁板结构特点,提出了其几何尺寸的确定方法。对典型加筋壁板结构基于成本-重量设计进行算例分析,讨论加筋间距、加强筋形状对成本-重量的影响。基于算例分析结论提出了成本-重量权衡的补偿函数,指导复合材料加筋壁板结构面向成本数字化制造和设计,为实现其高性价比设计提供依据。更多还原

【Abstract】 Composite material has been applied widely in the aeronautic and astronautic area because of light-weight and high-strength. However, the high manufacture cost restricts its further widely application. Reducing the structural weight and manufacture cost simultaneously, and improving the performance price ratio are the main purposes during the research of composite material. In the design and manufacture of composite structure, there is an integrated mould technique which could integrate hundreds of parts into only one part, reducing division, joint, installation time, structural weight, and manufacture cost. Composite stiffened panel is a typical integrated structure used in aircraft. In the early design stage, manufacture cost is the main considered parameter. Establishing a scientific estimation method of manufacture cost is beneficial to select material, optimize manufacture process, evaluate the performance and cost, and realize low cost optimum design. Most of the current research is limited to the structure performance. But there is little research considering manufacture cost as optimum design parameter. This paper mainly considers the balance between manufacture cost and weight of composite stiffened panel. The detailed contents are listed as following.1. According to the structural characters of composite stiffened panel, the estimation method of manufacture time of integrated mould process is presented. By considering the first order dynamic principle and power law, the unknown parameters in the estimation equations are determined. Composite panel with waved stiffeners is studied to verify the accuracy of estimation model for manufacture cost. Moreover, the method of selecting estimation variables is introduced. The theoretical estimation method of manufacture cost for composite stiffened panel is presented.2. The main factors which are related to the manufacture cost during the mould process of composite stiffened panel are analyzed. The cost estimation methods for every parameter are presented. Based on the above discussion, the cost estimation model for composite stiffened panel is established. The three different integrated mould processes for composite panel with T stiffener are studied to verify the applicability of this model. This estimation method is beneficial to direct the design of various composite structures.3. The effect of structural complexity to the manufacture cost is analyzed. The estimation equations of complexity effect for seven typical stiffened panels are listed. According to the practical engineering, the parameters in the estimation equations are modified. Based on the characters of mould process, a scientific estimation method of curing time is presented. Also how the localization for tools affects to time of matching moulds is studied.4. The stability requirement and manufacturability for the design of composite stiffened panel under compressive stress and shear force are analyzed. The theoretical results are compared to the results of ANSYS finite element method.5. The manufacture cost and structural weight are selected as optimum parameters. The optimum design method of composite stiffened panel under compressive stress and shear force is presented. According to the typical forming method of stiffened structure, the detailed process plan suitable for practical engineering is listed. The method of determining the geometrical shape of seven typical stiffeners is introduced. Various factors which affect the optimum design of composite stiffened panel are analyzed based on practical case and the results are matched perfectly. The optimum function of manufacture cost and structural weight are built to realize the low cost design of integrated composite stiffened panel.更多还原