NSF East Asia and Pacific Summer Institute (EAPSI) for FY 2013 in Japan

这一行动资助弗吉尼亚理工大学的Kenneth Brown于2013年夏天在东京的日本宇宙航空研究开发机构进行了一个工程学研究项目。该项目的标题是“开发一种新颖的多孔壁风洞，对低噪音风力涡轮机、飞机和海军舰艇产生影响。”目前，世界上只有两个风洞采用了新型混合消声测试段，之所以这样命名，是因为它集成了一个类似于传统风洞的空气动力学封闭式测试段，其声学开放测试能力类似于通过使用薄而多孔的芳纶®布墙的开放式喷气风洞。由于这样的测试段为空气声学研究的进步提供了重要的机会，弗吉尼亚理工大学的稳定性风洞开发了一种高保真方法，以事先修正升力干扰和阻塞的压力数据，该方法采用完全基于基本原理和独立测量的物理特性的面板方法模拟。日本宇宙航空研究开发机构的低速风洞也开发了一种修正方法，但它的基础与稳定风洞建立的基础不同。目前的研究旨在将两个风洞的空气动力学数据结合在一起，产生一种统一的方法来修正多孔壁、混合消声测试段的压力数据。这次研究之旅的另一个影响是弗吉尼亚理工大学的稳定风洞和日本宇宙航空研究开发机构之间的合作，这两个组织都处于空气动力学和空气声学研究的前沿。鉴于这两个风洞是世界上仅有的两个采用混合试验段的风洞，此次研究合作为指导空气声学研究提供了机会，为混合试验段建立了统一的气动修正方法。准确评估这些测试段的空气动力特性，再加上这些测试段提供的详细声学数据的同步测量，为开发风力涡轮机叶片、高速列车、飞机、汽车、潜艇和其他新旧技术提供了独特的机会。在这些领域中的每一个领域，都必须精确地在高性能空气动力学和低噪声发射声学之间取得平衡。将风洞测量的这两个方面合并到一个测试段中具有广泛的好处，并吸引了诸如NASA、DLR和ONERA等世界领先研究组织的研究兴趣。EAPSI奖学金的更广泛影响包括为研究员提供美国以外的第一手研究经验；介绍各自所在地的科学、科学政策和科学基础设施；以及了解社会、文化和语言。这些活动符合NSF的目标，即在其科学家、工程师和教育工作者的职业生涯早期为国际合作进行教育，从而确保拥有一支具有全球意识的美国科学队伍。此外，研究结果将通过研究员的论文以及研究员的其他出版物和研讨会来传播。通过这些手段，认为混合试验段可能成为下一代风洞结构是可行的，拓宽了气动声学界的研究能力。

This action funds Kenneth Brown of Virginia Tech to conduct a research project in Engineering during the summer of 2013 at the Japan Aerospace Exploration Agency in Tokyo. The project title is "Development of a Novel, Porous-Walled Wind Tunnel with Implications for Low Noise Wind Turbines, Aircraft, and Naval Vessels." The host scientist is Dr. Kazuomi Yamamoto.There are yet only two wind tunnels worldwide to employ the novel hybrid anechoic test section, named as such because it integrates an aerodynamically closed test section similar to those of traditional wind tunnels with an acoustically open testing capability similar to that of open jet tunnels through the use of thin, porous Kevlar® cloth walls. Due to the significant opportunity for advances in aeroacoustics research that such a test section affords, Virginia Tech's Stability Wind Tunnel has developed a high fidelity method to a priori correct pressure data for lift interference and blockage that employs a panel method simulation derived entirely from first principles and independently measured physical properties. The Japan Aerospace Exploration Agency's Low Speed Wind Tunnel has also developed a correction method, but it derives from a different basis than that established at the Stability Wind Tunnel. The current research aims to join aerodynamic data from both wind tunnels to produce a unified method for correcting pressure data in porous-walled, hybrid anechoic test sections. Another impact of the research trip is the collaboration produced between Virginia Tech Tech's Stability Wind Tunnel and the Japan Aerospace Exploration Agency, both of which organizations are on the forefront of aerodynamics and aeroacoustics research. Given that these two tunnels are yet the only two wind tunnels worldwide to employ the hybrid test section, this research collaboration provides an opportunity to direct the course of aeroacoustics research by establishing a unified aerodynamic correction method for hybrid test sections. An accurate evaluation of the aerodynamic characteristics of such test sections, when combined with the simultaneous measurement of detailed acoustic data that such test sections afford, provides unique opportunities in the development of wind turbine blades, high-speed trains, aircraft, automobiles, submarines, and other new and old technologies. In each of these fields, the balance between high performance aerodynamics and low noise emission acoustics must be struck with precision. Incorporating these two aspects of wind tunnel measurement into one test section has widespread benefits and attracts research interest from leading world research organizations such as NASA, DLR, and ONERA. Broader impacts of an EAPSI fellowship include providing the Fellow a first-hand research experience outside the U.S.; an introduction to the science, science policy, and scientific infrastructure of the respective location; and an orientation to the society, culture and language. These activities meet the NSF goal to educate for international collaborations early in the career of its scientists, engineers, and educators, thus ensuring a globally aware U.S. scientific workforce. Furthermore, the results of the research will be disseminated through both the Fellow's thesis and additional publications and seminars by the Fellow. Through these means, it is feasible to think that hybrid test sections may emerge as the next generation wind tunnel configuration, broadening the research capability of the aeroacoustics community.