对高度灵活的机翼进行几何非线性高保真航空结构优化
Alasdair C Gray1, Graeme J Kennedy2, Joaquim R R A Martins1
1Department of Aerospace Engineering, University of Michigan, Ann Arbor, MI USA.
概括
这项研究引入了一种新的方法,可以使用非线性模型同时优化飞机机翼形状和结构. 这种方法准确地解释了高比例翼的极端灵活性,这对于高效的飞机设计至关重要.
科学领域:
- 航空航天工程 航空航天工程
- 计算力学 计算力学 计算力学
- 优化理论 优化理论
背景情况:
- 多学科设计优化 (MDO) 的进步使得同时使用高保真模型进行空气动力学和结构翼设计.
- 当前的MDO方法准确地取消了阻力和质量,但在高面积比的翅膀中与几何非线性行为作斗争.
- 线性结构分析不足以建模下一代飞机机翼的极端灵活性和非线性.
研究的目的:
- 通过使用高保真度几何非线性模型首次同时优化机翼空气动力学形状和结构尺寸.
- 开发和实施用于非线性结构分析和气弹性合的计算工具.
- 研究几何非线性对高度灵活的飞机机翼设计和性能的影响.
主要方法:
- 实现了一种新的几何非线性外元素,一个高效的非线性解决器,以及硬化外的构成模型.
- 通过几何非线性转移方案将非线性结构分析与计算流体动力学 (CFD) 结合起来.
- 一个单通道商用运输飞机机翼的优化,具有547个设计变量和1277个约束.
主要成果:
- 优化的设计表现出极大的灵活性 (面积比> 19,偏移> 30%半径).
- 几何非线性对空气动力学性能,平面形状和飞机总体质量的影响最小.
- 布拉齐尔效应是一种非线性现象,它引入了线性分析所忽略的显著的内部负载,因此需要非线性方法来实现可行的设计.
结论:
- 开发的框架为设计下一代高比例翼提供了计算基础.
- 通过几何学非线性分析利用极端的机翼灵活性是设计更高效的飞机的关键.
- 这项研究可以通过将极端灵活性视为机会而不是约束来追求创新的翼设计.
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