EAGER: Acquisition of a Tomographic Particle Image Velocimetry System for Fluid-Structure Interaction Investigation of Active Blowing on Deformable Surfaces

多年来，主动吹气方法在延迟分离、升力增强和降噪方面取得了巨大的进步，但与高质量流量要求相关的一个主要障碍限制了它们在飞机平台上的使用。解决这一问题的一个潜在方法是综合和利用两种看似独特的主动流动控制方法，即提供连续机翼轮廓的可变形襟翼和主动上表面吹气，以开发更有效的主动流动控制系统，从而提高飞机的性能和操纵性。该项目的主要目的是调查和确定控制可变形表面上主动吹气性能的关键因素。该项目还将支持将研究与研究生和本科教育相结合，并将吸引、教育和帮助留住多样化的科学家/工程师队伍，包括来自合作机构的代表不足的少数族裔。该项目的目标是进行一项实验性的流动-结构相互作用调查，以影响我们对影响上表面后缘吹气的可变形襟翼附近相干结构形成和发展的关键参数的理解。由于控制流动的方程的高度复杂性，计算研究很少。针对主动吹气在可变形表面上的相干结构，实验结果也很稀疏；因此，本项目将在低速风洞中为这一应用建立一个详细的非定常流动-结构相互作用的实验数据库，使用最先进的层析粒子图像测速系统来获得速度。这些结果可以用来发展对问题的物理理解，并改进计算工具。该项目将一)确定支配可变形襟翼主动吹气性能的特性(可变形襟翼上不同的缝隙几何形状、缝隙高度、吹气强度和雷诺数)，以及二)确定和量化几何形状、激励频率和吹气强度对相干结构形成和发展的影响。该项目由流体动力学和既定的激励竞争研究计划(EPSCoR)共同资助。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Active blowing methods have shown tremendous improvements in delay separation, lift enhancement and noise reduction over the years, however a major roadblock associated with high mass flow requirements has restricted their use on aircraft platforms. One potential method to resolve this issue is to synthesize and utilize two seemingly unique active flow control methods, a deformable flap providing a continuous wing contour and active upper-surface blowing, to develop a more efficient active flow control system that can enhance aircraft performance and control. The primary aim of this project is to investigate and determine the key factors governing the performance of active blowing on deformable surfaces. The project will also support the integration of research with graduate and undergraduate education and it will attract, educate and help retain a diverse pool of scientists/engineers including underrepresented minorities from partner institutions.The goal of this project is to conduct an experimental flow-structure interaction investigation to impact our understanding of the key parameters that effect the formation and development of coherent structures near deformable wing flap with upper-surface trailing-edge blowing. Computational studies are scarce due to the high complexity of the equations that govern the flow. Experimental results focused on the coherent structures of active blowing on deformable surfaces are also sparse; therefore, the current project will produce a detailed experimental database for unsteady flow-structure interaction for this application in a low-speed wind tunnel using a state-of-the-art tomographic particle image velocimetry system to obtain velocities. These results can be used to develop a physical understanding of the problem and to improve computational tools. The project will i) determine the properties (varying slot geometry on the deformable flap, slot-height, blowing intensity and Reynolds number) that govern the performance of active blowing on deformable flaps and ii) identify and quantify the effects of geometry, frequency of actuation and blowing intensity on the formation and development on coherent structures. This project is jointly funded by the Fluid Dynamics and the Established Program to Stimulate Competitive Research (EPSCoR) programs.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.