激励特性对零质量射流的影响  

Effects of Excitation Characteristics on Synthetic Jets

作　　者：祝健[1] 康顺[1] 王晓东[1] 

机构地区：[1]华北电力大学电站设备状态监测与控制教育部重点实验室,北京102206

出　　处：《工程热物理学报》2017年第6期1217-1223,共7页Journal of Engineering Thermophysics

基　　金：自然科学基金项目(No.51576065);中央高校基本科研业务费项目(No.JB2015RCY05)

摘　　要：零质量射流是一种主动流动控制技术,具有结构紧凑,无需外界气源等优势。为了把零质量射流用于控制风电叶片表面流动,需要理解和掌握零质量射流的一些基本特征。本文采用求解雷诺平均NS方程的方法,以静止环境中的二维零质量射流为研究对象,研究4种激励速度和4种激励频率时零质量射流对流场扰动的基本特征,并对流场结构进行了拓扑分析。结果表明,零质量射流会在孔口处产生旋涡对,旋涡对在自身的诱导作用下不断向外扩展;由于射流速度的周期性变化,在孔口下游轴线产生鞍点,激励速度越大,鞍点运动速度越快,距孔口距离越远;激励频率越大,旋涡最大涡量值越大,涡核中心距孔口距离越近,涡核间距越小。Zero-net-mass-flux-jet, also known as Synthetic jets, arises as an emerging technology of active flow control, which has serval advantages, including compact structures and independence of jets source. In order to apply synthetic jets to the surface flow control of wind turbine blades, insightful understanding of the basic characteristics of synthetic jets is required. The excitation characteristics of two dimensional synthetic jets in a stationary flow is investigated at four different excitation velocities and four different excitation frequencies by using Reynold-averaged NS （RANS） simulations and topological analysis. Simulation results show that a vortex pair is generated from the inlet of orifice. The vortex pair extents in scale under self-induction with the transportation. A saddle point is generated at the downstream axis of the orifice due to the periodic variation of the excitation velocity. The movement of the saddle point and the distance from the orifice increase with the excitation velocity increasing. With increasing of the excitation frequency, the maximum of vortieity increases. Both the distances between vortex cores and from the vortex core to the orifice exit decrease.

关 键 词：零质量射流 激励速度 激励频率 CFD 

分 类 号：TK83[动力工程及工程热物理—流体机械及工程]