分类: 材料科学 >> 复合材料 分类: 力学 >> 固体力学 分类: 航空、航天科学技术 >> 飞行器制造技术 提交时间: 2024-04-09
摘要: 单向纤维增强塑料(UD-FRP)的力学性能受到内部微缺陷的影响,如随机纤维排列、纤维错位和微空隙。本研究旨在通过计算微观力学研究这些多个微观缺陷如何相互作用,以及它们如何影响UD-FRP的强度和失效机制。通过对具有代表性的体积单元进行有限元分析,模拟了失效行为;对于不同的载荷及其组合,考虑了基体和界面的破坏。研究发现,这些微观缺陷显著削弱了UD-FRP沿纵向的抗压强度。特别是纤维波纹度放大了纤维排列的影响,而微空隙则减小了这种影响。此外,纤维排列和微空隙显著削弱了UD-FRP的横向拉伸和压缩强度。此外,横向和纵向剪切强度受微孔隙的显著影响,但只有纵向剪切受纤维排列的影响,这种影响也因微孔隙而减弱。最后,得到了纵向压缩和横向荷载共同作用下的损伤包络线,并与Tsai Wu失效准则进行了比较。结果表明,Tsai Wu准则可以有效地估计这种双轴加载条件下的失效包络线。
分类: 计算机科学 >> 计算机软件 提交时间: 2022-12-07
摘要: For real parameter single objective optimization, Differential Evolution (DE) and Covariance Matrix Adaptation Evolution Strategy (CMA-ES) both perform powerfully. Nevertheless, in the field of real parameter single objective optimization, it is impossible for a given algorithm to perform well in all fitness landscapes. Practice has proved that ensemble of different algorithms may lead to improvement in solution. In this paper, based on two famous population-based metaheuristics - LSHADE-EpSin and HS-ES, we propose ensemble with successively executed constituent algorithms - HS-ES-DE. In our algorithm, HS-ES is replaced by L-SHADE-EpSin after stagnation is detected. Beside our HS-ES-DE, 12 population-based metaheuristics are involved in our experiments in which three benchmark test suites are employed. Experimental results show that our algorithm is very competitive.