Assessment of geometrically-nonlinear effects in aircraft loads

目前对飞机载荷的研究是基于线性结构动力学建模。这是一个有效的假设相对刚性的机翼，但它未能捕捉一些关键的影响，因为机翼的展弦比变得更高。它们包括机翼的几何硬化，随着几何变形而产生的气动力旋转，以及由于几何变化而引起的空气动力和惯性特性的变化等。为了研究这在未来更轻、更灵活的飞机机翼设计中的相关性，该项目将解决以下问题：-开发能够结合复杂阵风和机动载荷几何非线性的分析工具-计算高展弦比机翼设计中有无几何非线性的载荷，包括对设计的主要影响的分析。该分析方法应适用于现有的线性分析飞机有限元模型，并有效地捕捉由于大变形而引起的气动形状的相关变化。最后，该项目将对与非线性（时域）分析相关的计算成本进行评估，并提出生成生产就绪计算解决方案的策略

Current practice on aircraft loads is based on linear structural dynamics modelling. This is a valid assumption for relatively stiff wings, but it fails to capture some key effects as the aspect ratio of the wings becomes higher. They include the geometric stiffening of the wings, the rotation of the aerodynamic forces as they follow the deforming geometry, and changes on both the aerodynamic and the inertia characteristics due to large geometrical variations, among others. To investigate the relevance that this could have in the design of future lighter and more flexible aircraft wings, this project will address the following problems:- Development of analysis tools capable of incorporate geometric nonlinearity on complex for gust and manoeuvre loads - Computation of loads with and without geometric nonlinear on high aspect ratio wing design, including an analysis of the main implications on design.The analysis methods should apply to existing aircraft finite-element models, which are designed for linear analysis, and efficiently capture any relevant changes on the aerodynamic shapes due to the large deformations. Finally, the project will carry out an assessment of the computational costs associated to nonlinear (time-domain) analysis and propose strategies to generate production-ready computational solutions