相对于传统的几何外形优化技术，流动控制最有希望在未来提升飞行器气动性能。本团队创新提出了一种新型协同射流技术，可以非常小的能耗而极大增加升力、减小阻力、推迟失速迎角，特别是目前唯一能在巡航状态低攻角附着流状态下大幅提升计及功耗损失的升阻比与升力特性的新型流动控制技术。但是，目前针对协同射流的湍流掺混机理及参数影响机制尚不清楚，尤其是对脉冲协同射流研究处于空白。为此，本项目拟结合风洞精细试验和大涡模拟手段，进行3个基本内容研究：（1）协同射流湍流剪切层结构及其与主流的掺混发展过程；（2）不同流动参数下逆压梯度对协同射流剪切层的影响机制；（3）协同射流翼型在低攻角附着流状态下性能提升的流动机理及设计准则。最终通过试验与计算结果的细致对比，揭示高升阻比效应的湍流掺混机理与影响机制，研究成果对未来高性能/低能耗飞行器设计有重要的指导意义。

Active flow control is considered as a promising direction to improve airfoil aerodynamic performance beyond the conventional geometry manipulation. Recently, the Co-flow jet (CFJ) airfoil is shown to achieve extraordinary performance enhancement with drastic increase of lift coefficient, drag reduction, and stall angle of attack augment at very low energy expenditure. In particular, the recent numerical study indicates that the CFJ airfoil is able to significantly improve the aerodynamic efficiency and lift coefficient at cruise conditions when the flow is benign with low angle of attack. However, there is a lack of study to understand the fundamental physics of the CFJ airfoil working mechanism, in particular for the pulsed co-flow jet. We propose to investigate the following research subjects : 1) the mixing process and mixing layer structures with jet dissimilarity; 2) adverse pressure gradient effects; 3) CFJ airfoil performance enhancement mechanism at cruise conditions for attached flow at low angles of attack. The research approach is based on detailed comparisons between wind tunnel experiments at different angles of attack with companion Large Eddy Simulations (LES). The proposed research will be the first comprehensive study of its kind, which will lay the foundation for future high-performance aircraft with extraordinary aerodynamic performance.