Identification, characterisation and reduction of noise sources from flaps and their components

航空航天行业在加拿大经济中发挥着非常重要的作用，在创新方面处于领先地位，研发投资是加拿大制造业平均水平的7倍。在航空业，飞机噪音排放及其对社区的影响仍然是该行业发展的一个重要关切和风险。航空专家和监管机构认识到，要实现预计到2025-2030年的空中交通增长，将需要大幅减少飞机噪音排放。对于中小型商用飞机，如庞巴迪制造的飞机，机身噪声的主要来源是起落架和高升力装置(如板条和襟翼)。这个项目的重点是机翼襟翼系统产生的噪音。需要解决的关键挑战之一是更好地了解襟翼系统产生的噪声排放的性质，以及如何减少不同的噪声源。机体部件产生的噪声是一个复杂的现象，涉及到流体力学、空气动力学、声学以及三个学科之间的相互作用。虽然计算气动声学(CAA)可以提供一些见解，但气动声学领域仍然在很大程度上依赖于风洞实验和飞行试验来基本理解这些现象和验证CAA模拟。该项目将主要包括风洞测试，并由工业合作伙伴庞巴迪的CAA模拟提供支持。通过这种方式，该项目的另一个重要贡献将是能够改进和验证在设计新飞机时使用的CAA工具。实验将考虑襟翼系统中可能导致不同噪声产生机制的一些因素，包括襟翼边缘和襟翼轨迹致动器。这将被考虑用于没有和有后掠的机翼模型。这些结果将有助于更好地从根本上理解导致噪声排放的物理机制，为CAA验证提供详细的实验数据库，并为未来的飞机设计提供更好的最佳实践建议。

The aerospace sector plays a very important role in the Canadian economy and leads in innovation with 7 times the Canadian manufacturing sector average in R&D investment. In aviation, aircraft noise emission and how it affects communities remain an important concern and risk for growth of the industry. Aviation experts and regulators recognize that enabling the growth in air traffic anticipated by 2025-2030 will require drastic reductions in aircraft noise emissions. For small to mid size commercial aircraft, such as the ones manufactured by Bombardier, the dominant sources of airframe noise are the landing gears and high-lift devices (e.g., slats and flaps). The focus of this project is on the noise produced from the flap system of the wing. One of the key challenges to be addressed is to gain a better understanding of the nature of the noise emission due to the flap system and how the different sources of noise can be mitigated. Noise generation from airframe components is a complex phenomena that involves fluid mechanics, aerodynamics, acoustic and interactions between the three disciplines. While computational aeroacoustics (CAA) can provide some insights, the field of aeroacoustics still relies heavily on wind tunnel experiments and flight tests for fundamental understanding of the phenomena and validation of CAA simulations. This project will consist primarily of wind tunnel tests, supported by CAA simulations by the industrial partner Bombardier. In this manner, an additional important contribution from the project will be to enable improvements and validation of the CAA tools used in the design of new aircraft. The experiments will consider a number of elements from the flap system that can lead to different noise generation mechanisms, including the flap edge and flap track actuators. This will be considered for a wing model without and with sweep. The results will lead to better fundamental understanding of the physical mechanisms responsible for noise emission, a detailed experimental database for CAA validation and improved best practice recommendation for future aircraft design.