The Fast Simulation of Highly Flexible Flight Dynamics

有限元方法和计算流体力学相结合的形式可以用来模拟高度灵活的飞机的飞行动力学，但这将导致一个非常昂贵的计算问题，即使使用高性能计算资源也可能需要数小时才能解决。拟议项目的目的是通过使用替代的低阶方法来降低高度灵活的飞机的联合飞行动力学和气动弹性分析的计算成本。该项目最初将涉及对低阶结构动力学和流体动力学方法的最新研究。根据文献审查的结果，将选择在计算机代码内进行调查、推广和实施的方法。然后，代码将被验证，最有可能的是使用从巴西航空技术研究所的一个团队制造的高度灵活的模型飞机上收集的数据。与“玩具”案例相比，由于需要能够对完整的模型进行建模，因此代码可能会变得复杂。一旦得到验证，代码将与当前的方法进行比较。该代码还将用于调查设计和控制问题。例如，飞机不同部件之间的大弹性变形的耦合或柔性飞机的稳定性控制方法。这个项目的动机是需要提高飞机的效率。为了做到这一点，必须使用更轻的机身和更高的纵横比。为了使用传统的飞行动力学定律，机身必须足够坚固，使得气弹和飞行动力学的频率不同。通过消除这一刚度约束，可以以广泛考虑气动弹性和飞行动力学之间的耦合为代价来设计更高效的飞机。分析这一点目前具有挑战性，因此制约了该行业提高飞机效率的能力。

A combined formulation of the finite element method and computational fluid dynamics could be used to simulate the flight dynamics of highly flexible aircraft, but this would result in a very computationally expensive problem which may require many hours to solve even with high performance computing resources. The purpose of the proposed project is to reduce the computational cost of the analysis of combined flight dynamics and aeroelastics for highly flexible aircraft through the use of alternative, lower order methods. The project would initially involve investigation into the state of the art low order structural dynamics and fluid dynamics methods. Based on the outcome of the literature review, methods would be chosen to investigate, extend and implement within a computer code. The code will then be verified, most probably using data collected from a highly flexible model aircraft built by a team at the Institute of Aeronautical Technology in Brazil. It is likely that the code may become complex due to the need to be able to model a full model in comparison to a "toy" case. Once verified, the code will be compared to current methods. The code will also be used to investigate design and control problems. For example, the coupling of large elastic deformations between different parts of an aircraft or stability control methods for flexible aircraft. The motivation for this project is the need to increase aircraft efficiency. In order to do this, lighter airframes and higher aspect ratios must be used. In order for traditional flight dynamics laws to be used, the airframe must be stiff enough that the frequencies of the aeroelastics and the flight dynamics are dissimilar. By removing this stiffness constraint, more efficient aircraft may be designed at the cost of extensive consideration of the coupling between aeroelastics and flight dynamics. Analysing this is currently challenging, and is therefore a constraint the industry's ability to improve aircraft efficiency.