Aeroacoustics of Dynamic Stall

动态失速气动声学

• 批准号: EP/X019284/1
• 负责人: Mahdi Azarpeyvand
• 金额: $ 87.22万
• 依托单位: University of Bristol
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FX019284%2F1
• 关键词: Aeroacoustics; Dynamic; Stall

It is well established that long-term exposure to aircraft and wind turbine noise is responsible for many physiological and psychological effects. According to the recent studies, noise not only creates a nuisance by affecting amenity, quality of life, productivity, and learning, but it also increases the risk of hospital admissions and mortality due to strokes, coronary heart disease, and cardiovascular disease. The World Health Organization estimated in 2011 that up to 1.6 million healthy life years are lost annually in the western European countries because of exposure to high levels of noise. The noise is also acknowledged by governments as a limit to both airline fleet growth, acceptability of Urban Air Mobility, operation and expansion of wind turbines, with direct consequences to the UK economy.With regards to aerodynamic noise, aerofoil noise is perhaps one of the most important sources of noise in many applications. While aerofoils are designed to achieve maximum aerodynamic performance by operating at high angles of attack, they become inevitably more susceptible to flow separation and stall due to changing inflow conditions (gusts, wind shear, wake interaction). Separation and stall can lead to a drastic reduction in aerodynamic performance and significantly increased aerodynamic noise. In applications involving rotating blades, the near-stall operation of blades, when subjected to highly dynamic inflows, gives rise to an even more complex phenomenon, known as dynamic stall. While the very recent research into the aerodynamics of dynamic stall has shown the complexity of the problem, the understanding of dynamic stall noise generation has remained stagnant due to long-standing challenges in experimental, numerical and analytical methods. This collaborative project, which includes contributions from strong industrial and academic advisory boards, aims to develop new understanding of dynamic stall flow and noise and develop techniques to control dynamic stall noise. The team will make use of the state-of-the-art experimental rigs, dedicated to aeroacoustics of dynamic stall and GPU-accelerated high-fidelity CFD tools to generate unprecedented amount of flow and noise data for pitching aerofoils over a wide range of operating conditions (flow velocity, pitching frequency/amplitude, etc.). The data will then be used to identify flow mechanisms that contribute to the different aerofoil noise sources at high angles of attack, including aerofoil unsteady loading and flow quadrupole sources, and detailed categorisation of dynamic stall regimes. A set of new frequency- and time-domain analytical tools will also be developed for the prediction of dynamic stall noise at different dynamic stall regimes, informed by high-fidelity experimental and numerical datasets. This project will bring about a step change in our understanding of noise from pitching aerofoils over a wide range of operations and pave the way to more accurate noise predictions and development of potential noise mitigation strategies.

众所周知，长期接触飞机和风力涡轮机噪声是许多生理和心理影响的原因。根据最近的研究，噪声不仅通过影响便利性，生活质量，生产力和学习来造成滋扰，而且还增加了由于中风，冠心病和心血管疾病引起的住院和死亡率的风险。世界卫生组织在2011年估计，由于暴露于高水平的噪音，西欧国家每年在西欧国家每年损失多达160万个健康的人生年。政府还承认噪音是航空公司车队增长的限制，城市空气流动性的可接受性，风力涡轮机的运行和扩展，对英国经济的直接后果。就空气动力学噪音而言，Airofoil噪声可能是许多应用中最重要的噪声来源之一。虽然Aerofoils旨在通过以高攻击角度运行来实现最大的空气动力性能，但由于流入条件的变化（阵风，风剪，唤醒相互作用），它们不可避免地变得更容易受到流动分离和失速的影响。分离和失速会导致空气动力学性能的急剧下降，并显着增加空气动力学噪声。在涉及旋转叶片的应用中，叶片的近台操作在高度动态流入时会产生更复杂的现象，称为动态失速。尽管最近对动态失速的空气动力学的研究表明了问题的复杂性，但由于在实验，数值和分析方法方面的长期挑战，对动态失速噪声产生的理解仍然停滞不前。这个合作项目包括强大的工业和学术咨询委员会的贡献，旨在发展对动态失速流和噪声的新理解，并开发技术以控制动态失速噪声。该团队将利用最先进的实验钻机，专门用于动态失速和GPU加速的高保真CFD CFD工具的空气声学，以生成前所未有的流量和噪声数据，以在多种操作条件（流动性，流动频率/振动频率等）上倾斜空气层。然后，数据将用于识别以高攻击角度有助于不同的气压噪声源的流动机制，包括Aerofoil Unsteady载荷和流动四极杆源，以及动态失速机制的详细分类。还将开发一组新的频率和时域分析工具，以预测不同动态失速机制的动态失速噪声，这是由高保真实验和数值数据集提供的。该项目将使我们对噪声的理解有所改变，从俯仰螺旋装饰上的噪声中，并为更准确的噪声预测和潜在降解策略的发展铺平了道路。