树脂基复合材料曲面结构件固化变形数值模拟
Numerical simulation of curing deformation of resin matrix composite curved structure

为了研究树脂基复合材料曲面结构件的固化变形过程, 首先分析了碳纤维增强树脂基复合材料在固化过程中密度、模量、热膨胀系数、比热容及热传导系数等材料物性的变化, 并将这些变化引入到数值模拟当中。接着, 针对复合材料复杂曲面结构件, 提出了利用定常流动的流线方程构建曲线坐标系的新方法。然后, 根据建立的曲线坐标系, 运用有限元法计算了某轻型飞机机翼上蒙皮板在固化过程中内部温度、固化度和内应力的分布情况以及材料物性随固化度的变化情况。最后, 计算了由于内部温度场和固化度场的不均匀、热膨胀系数的各向异性和固化引起的树脂体积收缩而导致的结构变形。结果表明:引入材料物性变化使固化过程的数值模拟更加合理、模拟结果更加精确, 利用定常流动的流线方程构建的曲线坐标系适用于复合材料曲面结构件的有限元分析。所得结论对研究树脂基复合材料的固化变形过程和各向异性复合材料复杂曲面构件的三维实体建模均具有指导意义。 In order to investigate the curing deformation process of resin matrix composite curved structure, first, the evolutions of physical properties such as density, modulus, thermal expansion coefficient, specific heat capacity and thermal conductivity et al during the curing process of carbon fiber reinforced resin matrix composites were analyzed, and those evolutions were introduced into the numerical simulation. Second, the new approach of constructing the curvilinear coordinate system by streamline equation of steady flow was proposed for the composite complex curved structure. Third, the distribution of internal temperature, curing degree and internal stresses, and evolution situations of material physical properties along with curing degree during the curing process of the skin plate of a light aircraft wing were calculated by finite-element method based on the curvilinear coordinate system constructed. Finally, the deformations of the structure caused by the uneven distributions of internal temperature field and cure degree field, anisotropy of thermal expansion coefficient and volumetric shrinkage of resin result from curing were calculated. The results show that the numerical simulation of curing process will be more reasonable and the simulation results will be more accurate when the evolutions of material physical properties are adopted, and the curvilinear coordinate system constructed by streamline equation of steady flow is applicable to the finite element analysis of composite curved structure.The conclusions have instruction significance to the research of curing deformation process of resin matrix composites and the establishment of three dimensional solid model of composite complex curved structure which is anisotropic. 国家"973"计划(2014CB046500)