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对旋转湍流射流的主动和被动控制进行了实验研究。初始旋流分布被证明是主导的自由射流演变的被动模式。通过减小涡核直径，在低于临界旋流数（S = 0.48）时实现了高强度旋流的一种表现形式--涡破裂。本文研究了低速冷射流中旋转湍流射流对单频平面波声激励的响应，结果表明，声激励的响应强烈地依赖于旋转数、激励Strouhal数、激励波的振幅和核心湍流度。在x/D = 9.0时平均中心线速度减少10%（剪切层动量厚度相应增加），这是通过大振幅内部平面波声激励实现的。根据流体动力学稳定性理论，在旋转自由射流中，负方位波数的螺旋不稳定波比平面波具有更大的放大率。因此，主动旋转剪切层控制，提出了包括任意螺旋度的波和模式的相互作用，通过多频强迫。
Passive and active control of swirling turbulent jets is experimentally investigated. Initial swirl distribution is shown to dominate the free jet evolution in the passive mode. Vortex breakdown, a manifestation of high-intensity swirl, was achieved at belo_r_critical swirl number (S = 0.48) by reducing the vortex core diameter. The response of a swirling turbulent jet to single-frequency, planeawave acoustic excitation was shown to depend strongly on the swirl number, excitation Strouhal number, amplitude of the excitation wave, and core turbulence in a low=speed cold jet. A 10% reduction of the mean centerline velocity at x/D = 9.0 (and a corresponding increase in the shear layer momentum thickness) was achieved by large amplitude internal plane-wave acoustic excitation. Helical instability waves of negative azimuthal wave numbers exhibit larger amplification rates than the plane waves in swirling free jets, according to hydrodynamic stability theory. Consequently, an active swirling shear layer control is proposed to include the waves of arbitrary helicity and the of modal interaction, through multifrequency forcing.