Abstract

The research evaluated constant stiffness (CS) and variable stiffness (VS) laminate composites using two simulated situations: static and bird strike analyses. The first example demonstrates that a plate with a hole exhibits better strength and stiffness when using VS laminate. The continuously changed fibre orientation creates variations in stiffness at different locations, allowing designers to adjust the distribution of internal loads to improve structural performance or reduce weight. The second example indicates that VS laminate skin on a wing's leading edge exhibits better resistance to bird impacts. This is because compared with the CS lay-up of composite materials, this kind of the VS lay-up (asymmetric unbalanced lay-up) makes the material matrix to have some nonzero coupling items, which is conducive to improving the impact resistance of the structure. Simulation results show that these VS composites reduce deformation and stress induced by bird strikes without increasing the weight or size of the components or adding additional structure.

摘要

该研究使用两种模拟情况评估了恒定刚度 (CS) 和可变刚度 (VS) 层压复合材料：静态和鸟击分析。第一个例子表明，带孔的板在使用 VS 层压板时表现出更好的强度和刚度。不断变化的纤维取向会在不同位置产生刚度变化，从而使设计人员能够调整内部载荷的分布以提高结构性能或减轻重量。第二个例子表明，机翼前缘上的 VS 层压蒙皮表现出更好的抗鸟类撞击能力。这是因为与复合材料的CS叠层相比，这种VS叠层（非对称不平衡叠层）使材料基体具有一些非零耦合项，有利于提高结构的抗冲击性。仿真结果表明，这些 VS 复合材料可减少鸟击引起的变形和应力，而无需增加部件的重量或尺寸或增加额外的结构。