EAGER: Improving the Aeroacoustic Properties of Hybrid Anechoic Wind Tunnels

EAGER：改善混合消声风洞的气动声学特性

• 批准号: 2012443
• 负责人: William Devenport
• 金额: $ 19.55万
• 依托单位: Virginia Polytechnic Institute and State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-01-15 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2012443&HistoricalAwards=false
• 关键词: EAGER; Improving; Aeroacoustic; Properties; Hybrid; EAGER; Improving; Aeroacoustic; Properties; Hybrid

Wind tunnels are a fundamental part of the engineering and scientific process used to develop quieter and more efficient aircraft, wind turbines, and other systems. The hybrid anechoic wind tunnel, introduced some 13 years ago, provides a way to substantially increase the accuracy and scope of wind tunnel tests concerned with flow generated noise. This configuration, which has already been adopted by a number of research facilities across the world relies on “acoustic windows” – large panels of tensioned fabric that are transparent to sound but largely impervious to flow. Such windows have been made from commercially available Kevlar fabric which has many desirable characteristics for this purpose, but the fabric was designed for composites manufacture. A Kevlar fabric explicitly designed for wind tunnel applications promises additional benefits – an even quieter test environment and embedded instrumentation that can monitor the flow. Under this project, an interdisciplinary team of textiles, acoustics, and aerodynamics researchers will conduct a short-term research program to develop these materials. This innovative, potentially high payoff effort, promises to bring the advantages of hybrid anechoic testing to national scale facilities and greatly enhance the development quieter and more efficient vehicles and systems. This project will also be dedicated to research education at the postdoc, graduate and undergraduate levels. This research is based upon the observation that Kevlar fabric used as acoustic windows generates noise at high frequencies (10kHz) that potentially limits the application of this technology in the context of national scale wind tunnel facilities that perform applied model scale testing for vehicle development by industry and government. The hypothesis is that the noise is made by pores in the fabric that serve no useful aeroacoustic function. Adjusting the weave to eliminate the pores requires the multi-disciplinary collaboration needed to perform a systematic study of the optimum fabric design for aeroacoustic applications. The work is being performed by a team of researchers from Virginia Tech, Florida Atlantic University, and NC State. The NC State group will use a research loom fabricate the needed modified fabrics and also investigate the feasibility of embedding sensors. Wind tunnel experiments directed at documenting and understanding the aeroacoustic performance of the fabrics will be performed at Virginia Tech, which will also provide input on sensor choices and requirements. Theoretical modeling and understanding of the nature of the acoustic source will be performed at Florida Atlantic University. Together this effort is expected to generate robust recommendations for optimal acoustic window design and embedded sensors that can be adopted by current and planned hybrid anechoic wind tunnels.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

风隧道是工程和科学过程的基本组成部分，用于开发更安静，更高效的飞机，风力涡轮机和其他系统。大约13年前引入的混合动脉风洞提供了一种方法，可以实质上提高与流动噪声有关的风洞测试的准确性和范围。这种配置已经被世界各地的许多研究设施采用，依赖于“声窗户” - 大量的张紧织物，它们透明了声音，但在很大程度上不渗透流动。此类窗户是由可商购的Kevlar织物制成的，该面料具有许多为此目的的理想特征，但该面料是为复合材料制造而设计的。针对风洞应用设计的凯夫拉尔织物有望提供其他好处 - 更安静的测试环境和可以监视流量的嵌入式仪器。在这个项目下，纺织品，声学和空气动力学研究人员组成的跨学科团队将进行一项短期研究计划，以开发这些材料。这项创新的，潜在的高收益工作有望将混合动力测试的优势带入国家规模的设施，并大大增强了更安静，更高效的车辆和系统的开发。该项目还将致力于博士后，研究生和本科级别的研究教育。这项研究基于以下观察结果：用作声窗的凯夫拉（Kevlar）面料会在高频（10kHz）下产生噪声，该噪声可能会限制该技术在国家规模风洞设施中的应用，这些设施对行业和政府进行了用于车辆开发的模型规模测试。假设是噪声是由织物中没有有用的气声功能的孔产生的。调整编织以消除毛孔，需要对用于空气声应用的最佳织物设计进行系统研究所需的多学科协作。这项工作是由弗吉尼亚理工大学，佛罗里达大西洋大学和北卡罗来纳州立大学的一组研究人员进行的。 NC州组将使用研究织机制造所需的修改织物，并研究嵌入传感器的可行性。旨在记录和理解织物的空气表现性能的风洞实验将在弗吉尼亚理工学院进行，该实验还将提供有关传感器选择和要求的意见。理论上的建模和对声学本质的理解将在佛罗里达大西洋大学进行。预计这项工作将共同为最佳的声学窗口设计和嵌入式传感器产生强大的建议，这些建议可以由当前和计划中的混合动力式风隧道采用。该奖项反映了NSF的法定任务，并被基金会的知识分子优点和更广泛的影响审查审查标准，通过评估来诚实地诚实地支持。