摘要
在半顶角为10°的圆锥前体尖端处布置一对等离子体激励器,通过占空循环控制技术实现了对圆锥前体力和力矩的近似比例控制,并对流动控制机理进行了讨论。采用静态和动态压力测量实验技术对圆锥前体各测量截面轴向压力分布进行测量,并对流场旋涡结构变化进行了二维粒子图像测速。实验在3.0m×1.6m低速低湍流度风洞中进行,迎角45°,基于圆锥段底面直径的雷诺数为5×104。实验结果表明,等离子体激励器关闭时圆锥前体涡流场非对称,当左、右舷等离子体激励器开启时,涡流场在双稳态之间转换;在占空循环控制下,不同周期同一相位的平均压力结果表明涡流场具有一定的周期性并且在2个稳态之间平缓变化,但变化幅度较原来的双稳态小。
Duty cycle modulation of the alternating blowing from two opposite facing plasma actuators on the leeward surface near the apex of a cone of semi-apex angle 10° to control the mean lateral force and moment and the flow control mechanisms are presented. The pressure distributions over the cone forebody are measured using steady and unsteady pressure-tappings, the primary state of the boundary layer is visualized by performing a 2D-PIV （particle image velocimetry） tests. The experiments were perfomed in a 3.0 m×1.6 m open-circuit wind tunnel at 45° angle of attack and Reynolds number of 5×104 based on the cone base diameter. The opposite bi-stable vortex patterns appear when the port or starboard actuator is activated while the other is kept off during the test. The phase-locked （locked to the plasma duty cycle） averaged flow induced by the duty-cycled plasma actuation is periodic and varies smoothly between two opposite states like the bi-stable states but much smaller in amplitude.
基金
高等学校博士学科点专项科研基金资助项目(200806990003
20096102120001)
西北工业大学基础研究基金资助项目(JC200901)
西北工业大学博士论文创新基金资助项目(CX201001)
中国博士后科学基金资助项目(20100471000)
关键词
细长体
非对称分离涡
大迎角空气动力学
等离子体
主动流动控制
粒子图像测速
slender body
asymmetric vortex flow
high angle of attack aerodynamics
plasma
active flow control
PIV （particle image velocimetry）
作者简介
刘锋，（1963-），男，教授，主要研究方向：气动弹性、涡轮发动机设计、燃烧、微重力下燃烧、两相流、旋涡稳定性及流动控制等，fliu@uci．edu
