合成射流低速射流矢量偏转控制的PIV实验研究

摘要

通过在二元矩形射流风洞出口两侧布置斜置扩张的斜出口合成射流激励器,并调整到合适的扩张角,在主射流未形成Coanda效应的前提下,利用合成射流非定常扰动来“激发”诱导主射流剪切层,使主射流发生矢量偏转.结合PIV测试技术,对合成射流在不同电压和频率参数下控制低速主射流的时均流场进行了测试.结果表明仅需改变激励器的电压和频率电参数,就可实现对主射流矢量偏转的主动控制.随电压的逐渐增加,可实现对主射流的比例偏转控制.频率变化对主射流矢量偏转角的影响较显著,在共振频率下可以获得最大的矢量偏转角.通过控制两侧激励器的“开—关”控制,可以实现对主射流矢量偏转的切换控制,PIV瞬态流场测试结果表明该切换过程是连续可控的.%Synthetic jet actuators with beveled orifices have been installed on both sides of a two dimensional rectangular jet wind tunnel,and have been adjusted to an appropriate angle.On the premise that the Coanda effect is not formed in the main jet,the main jet shear layer is induced by the unsteady disturbance of the synthetic jet,which causes the deflection of the main jet.By integrating with PIV test,the time-averaged flow field has been tested for low speed main jet controlled by synthetic jet actuator at different forcing voltages and frequencies.The results show that the active control of main jet vectoring deflection can be achieved only with the change of the forcing voltage and frequency.With the increment of the forcing voltage,the proportioned vectoring control of the main jet can be obtained.Forcing frequency has a significant effect on the vectoring angle of the main jet,and the maximal jet vectoring angle can be obtained at the resonance frequency of the actuator.Through "on-off" control on both sides of the synthetic jet actuator,the switching control of the main jet vector deflection can be achieved,and the process is continuous and controllable.