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利用在线式互相关ＰＩＶ（ＰａｒｔｉｃｌｅＩｍａｇｅＶｅｌｏｃｉｍｅｔｒｙ）系统，在低速风洞中对ＮＡＣＡ００１２翼型在雷诺数２．３９×１０５，０°和４°攻角下的近尾迹流动进行了详细测量。实验结果表明，翼型近尾迹存在有序的涡街结构，涡街在尾缘处形成后，在向下游的迁移中，会经历一个发展壮大、失稳破碎的演化过程，流动从有序走向无序。翼型的近尾迹是一种以旋涡的运动学特性和动力学机制为主导的流动现象。本文着重探讨了翼型尾缘处的涡街形成机理，尾迹内的流动机制，以及近尾迹的流动稳定性。
The near-wake flow of NACA0012 airfoil was measured in a low speed wind tunnel at an attack angle of 2.39 × 105,0 ° and 4 ° Reynolds number using a cross-correlation PIV (Particle Image Velocimetry) system. The experimental results show that there is an orderly vortex structure near the wake of the airfoil. After the vortex street is formed at the trailing edge, it undergoes an evolutionary process of growth and instability and fragmentation during its migration to the downstream. Disorderly. The near wake of the airfoil is a kind of flow phenomenon that is dominated by the kinematics and dynamics of vortices. This paper focuses on the mechanism of vortex shedding at the trailing edge of the airfoil, the flow mechanism in the wakes, and the flow stability of the wake.