Low-Frequency Unsteadiness of Pressure-Induced Turbulent Separated Flows

湍流边界层的分离和再附着在气动系统中是很常见的，往往不利于气动系统的性能。在高速流动的情况下，与分离和再附着流动相关的压力和速度的非定常可能导致振动、噪声甚至非定常热负荷。然而，目前的工程预测方法仍然往往不足以准确地模拟这些现象。因此，为了提高我们在技术应用中建模和最终控制这些流动的非定常方面的能力，需要更好地理解分离和再附着的物理学。***提出的研究计划的目标是进一步了解驱动压力诱导的湍流分离流的低频非定常行为的物理机制，并提出基于物理的策略来控制这种非定常。我们计划结合实验、数值和理论方法来实现这一目标

Separation and reattachment of turbulent boundary layers are common in aerodynamic systems and are often detrimental to their performance. The unsteadiness in pressure and velocity that is associated with separating and reattaching flows can lead to vibration, noise, and even unsteady thermal loads in the case of high-speed flows. Yet current engineering prediction methods are still often inadequate to accurately model these phenomena. A better understanding of the physics of separation and reattachment is therefore required in order to improve our capability of modeling and eventually controlling the unsteady aspects of these flows in technological applications.***The goal of the proposed research program is to further our understanding of the physical mechanisms that drive the low-frequency, unsteady behavior of pressure-induced turbulent separated flows and to propose physics-based strategies to control this unsteadiness. We plan to combine experimental, numerical, and theoretical approaches to achieve this goal.**