基于TR-PIV方法的格栅-空腔流动流场自激振荡空间特征研究  

Spatial distribution characteristics of self-excited oscillations in a grille-cavity flow field based on TR-PIV method

作　　者：张永昌 徐宇工[2] ZHANG Yongchang;XU Yugong(Transportation College, Inner Mongolia University, Hohhot 010070, China;School of Mechanical,Electronic and Control Engineering,Beijing Jiaotong University,Beijing100044,China)

机构地区：[1]内蒙古大学交通学院,呼和浩特010070 [2]北京交通大学机械与电子控制工程学院,北京100044

出　　处：《振动与冲击》2018年第23期234-240,共7页Journal of Vibration and Shock

基　　金：国家重点研发计划(2016YFB1200506-09);内蒙古自治区自然科学基金(2018BS05014);内蒙古大学高层次人才引进项目(22200-5175158)

摘　　要：格栅-空腔流动能够引起流场自激振荡现象,导致诸多工程问题。采用风洞实验方法对流场振荡的空间分布特征问题进行了研究;建立了格栅-空腔实验装置,使用时间分辨粒子图像测速系统(TR-PIV)对空腔不同展向截面的速度场进行了测量,分析了流场特定位置速度振荡的时频特征。研究结论表明:在格栅-空腔流动中,流场自激振荡频率在空间中均匀分布,其斯特劳哈尔数约为0. 37。在格栅外侧,振荡幅值沿来流方向呈增加-减小-增加变化;在格栅内侧,振荡幅值沿来流方向先增加后减小;振荡幅值沿展向呈对称分布,在展向平分面达到最大值,在空腔壁面处达到最小值。Grille-cavity flow can cause flow field self-excited oscillations to lead to various engineering problems.Here,wind tunnel tests were used to investigate spatial distribution characteristics of flow field oscillations.A grille-cavity test device was built.Using the time-resolved particle image velocity(TR-PIV)measurement system,velocity fields of the cavity’s sections in different spread directions were measured.The time-frequency characteristics of velocity oscillations at the specific positions of flow flied were analyzed.The results showed that in grille-cavity flow,the flow field self-excited oscillation frequencies are uniformly distributed in space and their Strouhal number is about0.37;on the outside of the grille,the oscillation amplitudes have a variation of increase-decrease-increase in flow direction;on the inside of the grille,the oscillation amplitudes increase firstly and then decrease;the oscillation amplitudes are symmetrically distributed along the spread direction to reach the maximum on the spread bisector plane,and the minimum on the cavity’s wall surface.

关 键 词：格栅-空腔流动 自激振荡 时间分辨粒子图像测速 空间分布 

分 类 号：O355[理学—流体力学]