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.
作者
张永昌
徐宇工
ZHANG Yongchang;XU Yugong(Transportation College, Inner Mongolia University, Hohhot 010070, China;School of Mechanical,Electronic and Control Engineering,Beijing Jiaotong University,Beijing100044,China)
出处
《振动与冲击》
EI
CSCD
北大核心
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)
