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缠绕复合材料结构分析是缠绕复合材料力学性能研究及应用的重要基础。发展了一种缠绕复合材料结构分析有限元方法,该方法基于缠绕复合材料细观刚度模型,通过建立细观刚度场与整体结构的映射关系,将缠绕复合材料细观刚度模型引入缠绕复合材料结构有限元分析中。采用各向异性单元,几何模型与网格划分等过程不需要进行复杂的处理,单元材料属性采用细观刚度模型计算,并通过已建立的细观刚度场和整体结构的映射关系输入。建立了缠绕复合材料结构有限元分析的流程,采用MATLAB程序编写了细观刚度场计算程序,采用ANSYS提供的APDL语言开发了几何建模、分网、读入刚度矩阵等相应分析程序,最后进行了算例分析。算例结果表明,缠绕复合材料内部各层应力应变呈周期性分布,应力应变在纤维交叉和波动区域有所变化,纤维波动对局部应力具有放大作用;纤维走向的交替造成内部剪切应力的正负交替;纤维弯曲引起的局部刚度下降造成局部的应变较大。与传统的经典层合板理论或有限元方法相比,在缠绕复合材料有限元分析中,采用基于傅里叶级数的细观刚度模型,可以反映材料内部细观结构对应力应变分布的影响;同时,方法简单,便于程序实现。
Structural analysis of wound composite material is an important foundation for the study and application of the mechanical properties of wound composite material. A finite element method for the structural analysis of wound composite materials is developed. Based on the meso-stiffness model of the wound composite material, the method establishes the relationship between the microscopic stiffness field and the overall structure, and introduces the meso-stiffness model of the wound composite material into the wound composite structure Finite element analysis. The use of anisotropic elements, geometric models and meshing does not require complex processing. The material properties of the elements are calculated using the meso-stiffness model and input through the established mapping relationship between the meso-stiffness field and the overall structure. The procedure of finite element analysis of the composite material structure was established. The program of calculating the meso-stiffness field was programmed by using MATLAB program. The APDL language provided by ANSYS was used to develop the corresponding analysis program of geometric modeling, sub-network and stiffness matrix reading, and finally Case study. The numerical results show that the stress and strain in the inner layers of the composite material are cyclical, the stress and strain change in the cross-section and the undulating area, and the fiber fluctuations amplify the local stress. The fiber orientation alternates with the positive shear stress Negative alternation; local stiffness caused by fiber bending caused by greater local strain. Compared with the classical theory of classical laminates or finite element method, the meso - stiffness model based on Fourier series can reflect the influence of the mesostructure on the stress - strain distribution in the composite material. At the same time, the method is simple, easy to program implementation.