等离子体激励器控制圆柱绕流的实验研究  

FLOW CONTROL OVER A CIRCULAR CYLINDER USING PLASMA ACTUATORS

作　　者：张鑫[1] 黄勇[2] 李华星[1] Zhang Xin;Huang Yong;Li Huaxing(School of Aeronautics,Northwestern Polytechnical University,Xi＇an 710072,China;China Aerodynamics Research and Development Center,Mianyang 621000,Sichuan,China)

机构地区：[1]西北工业大学航空学院,西安710072 [2]中国空气动力研究与发展中心,四川绵阳621000

出　　处：《力学学报》2018年第6期1396-1405,共10页Chinese Journal of Theoretical and Applied Mechanics

基　　金：装备预先研究资助项目(51313010204)

摘　　要：为了发展新型移动附面层控制技术,提升流动控制效率,采用粒子图像测速技术,开展了基于对称布局等离子体气动激励的圆柱绕流控制研究,获得了静止空气下,对称布局激励器诱导流场的演化过程,评估了来流条件下等离子体控制效果,通过等离子体诱导涡实现了虚拟移动附面层控制,分析了诱导涡随时间演化的过程,揭示了圆柱绕流等离子体控制机理.结果表明:(1)在静止空气下,对称布局激励器在刚启动瞬间,会在暴露电极两侧诱导产生一对旋转方向相反的启动涡;随着时间的推移,启动涡逐渐向远离壁面的方向运动;随后,激励器在暴露电极两侧产生了两股速度近似相等,方向相反的诱导射流,诱导射流在柯恩达效应的影响下,朝壁面方向发展.(2)当激励电压峰峰值为19.6 kV,激励频率3 kHz时,施加等离子体气动激励后,圆柱脱落涡得到了较好抑制,圆柱阻力系数减小了21.8%;(3)在来流作用下,对称布局激励器在靠近来流一侧,诱导产生了较为稳定的涡结构.诱导涡通过旋转、运动,促进了壁面附近低能气流与主流之间的掺混,抑制了圆柱绕流流场分离,实现了"虚拟移动附面层控制"效果.与传统移动附面层控制技术相比,基于等离子体气动激励的新型移动附面层控制技术不需要复杂、笨重的机构,不会带来额外的阻力,具有潜在的应用前景.In order to develop a novel technology of Moving Surface Boundary Layer Control （MSBLC） and promote efficiency of flow control technology, flow control over a circular cylinder using two Dielectric Barrier Discharge （DBD） symmetrical plasma actuators was investigated by PIV technology, force measurements and hot wire. The circular cylinder which had a diameter of 50 mm and a spanwise length of 480 mm was placed on the support sting. Here, two symmetrical DBD plasma actuators were mounted at the top and bottom of the circular cylinder respectively. The testing model which was made of aluminum was adopted as the covered electrode and was wrapped by the KAPTON film. The exposed electrodes were copper foil tape which was 2 mm wide and 0.02 mm in thickness. Firstly, time-resolved PIV results in still air indicated that a pair of the starting vortexes which were rotating in the opposite direction was induced as the symmetrical plasma actuator was just started to work. The starting vortexes rolled up and moved away from thewall with time. Then, a bi-directional wall jet on both sides of the exposed electrode was formed by the symmetrical plasma actuator. Due to Coanda Effect, the induced jet moved along the surface of circular cylinder. Secondly, the force and hot wire measurement results under incoming flow suggested that vortex shedding from the circular cylinder can be suppressed significantly by the symmetrical plasma actuators and the drag coefficient was decreased by 21.8 % at the wind speed of 10 m/s. Besides, it can be found that a steady vortex can be formed on the surface of cylinder thanks to the interaction effect between the incoming flow and the induced flow filed by plasma actuator. The induced vortex can transfer high momentum from main flow to the near-wall fluid by rotating and moving, enabling the boundary layer to withstand the adverse pressure gradient and prevent the separation around the circular cylinder and acting as the virtual MSBLC. Compared to the traditional MSBLC, the novel technol

关 键 词：移动附面层控制 流动控制 等离子体 介质阻挡放电 风洞实验 

分 类 号：V211[航空宇航科学与技术—航空宇航推进理论与工程]