The characteristics of the vortex cores over a 20°circular-cone forebody under plas-ma actuation are studied at 45°angle of attack.Two long strips of SDBD plasma-actuators are installed symmetrically on the plastic frontal cone near the apex.The length of the electrodes is 20 mm along the cone meridian with the leading edge located at 9 mm from the cone apex.Two AC power sources connected to the plasma actuator respectively.The peak-to-peak voltage and frequency are set at V p-p ≈14 kV and f ≈8.9 kHz,respectively.The input power for the plasma on is about 19.3 W.The induced jet flow is pointed at the windward side.Section velocity distribution and pressure distribution are measured in a low-turbulence 3.0 m×1.6 m low-speed open-circuit wind tunnel.The Reynolds number based on the base diameter of the circular cone is 5 ×104 . The effects of the plasma actuations on the flow physics,such as lateral force,vortex core center position,axial vorticity,vortex core radius,vortex sub-core radius,vortex maximum tangential velocity and circulation are studied.The actuation of plasma actuator on one side pushes the same-side boundary-layer separation point in the windward direction and pulls the other-side sepa-ration point in the leeward direction.The suction peak is decreased on the same side and increased on the other side.The separation shear layer and rolled-up vortex core move out on the same side and close in on the other side.In repetition wind tunnel runs of the same model,the flow asym-metry pattern remains unchanged for port-on and starboard-on,while may be changed for plasma-off coses.The plasma actuations tend to increase significantly the size of the vortex core and increase fairly the size of the vortex sub-core,thus,the vortex sub-core becomes more compact relative to the vortex core than that of plasma-off.Vortex core center may be biased from the mid-point be-tween the maximum tangential-velocity points along radial line passing through the vortex core center due to the plasma actuations.The plasma actuation may strengthen vortex maximum axial vorticity,in case the vortex is dispersed for plasma off.%在圆锥-圆柱组合体模型半顶角为10°的圆锥前体尖端附近布置介质阻挡放电等离子体激励器，采用正弦波高压电源进行等离子体定常开／关激励。实验在3．0m×1．6m 的直流式风洞中进行，迎角固定在45°，基于圆锥前体底面直径的实验雷诺数为5×104。对模型表面周向压力分布进行了测量，同时对测压截面处的空间涡流场进行了粒子图像测速。通过对截面压力分布和空间流场的 PIV 结果的分析，给出了侧向力、涡核中心位置、轴向涡量、涡核半径、次涡核半径、旋涡最大切向速度、环量等参数随等离子体激励的变化特性。结果表明：在等离子体激励的作用下，同侧的分离剪切层及其卷起的涡向外侧移动，同时另一侧的向着靠近模型的方向移动。同时激励器的作用使左舷侧涡心位置偏离次涡核的几何中心，且使得双侧的涡核和次涡核的尺寸增大。
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