明渠均匀流简易粒子图像测速技术浅析  

Analysis on Simple Particle Image Velocimetry Technology for Uniform Flow in the Open Channel

作　　者：李建林 Li Jianlin(State Key Laboratory of Hydraulics and Mountain River Development and Protection,Sichuan University Chengdu 610065,Sichuan)

机构地区：[1]四川大学水力学及山区河流开发与保护国家重点实验室,四川成都610065

出　　处：《陕西水利》2019年第2期16-18,共3页Shaanxi Water Resources

摘　　要：粒子图像测速系统PIV是一种近年兴起并发展迅速的非接触式流体测量方式,通过测量示踪粒子在很短时间间隔内的位移来间接地测量流场的速度分布,具有高精度、多点位和瞬时态等优点,但其需要高功率激光片光来定位速度剖面和照亮示踪粒子,高昂的价格和维修费用使得人们需要找到一种非激光照明式PIV作为替代。结合明渠均匀流的断面流速测量特点及工作原理,使用LED光照亮示踪粒子,并运用摄影原理窄束景深得到清晰的速度矢量场图形。经过分析发现,测量结果与理论公式所得值吻合良好,说明该技术在均匀流流态中具有较高精确性和实用性。The particle image velocimetry system,PIV is a non-contact fluid measurement method that has been rising and developed rapidly in recent years.It measures the velocity distribution of the flow field indirectly by measuring the displacement of the tracer particles in a short time interval.It has some advantages in high precision,multi-point and transient state,but it requires high power laser light to locate velocity profile and illuminate tracer particles.It takes high cost and maintenance costs to make us find a non-laser-illuminated PIV as an alternative.Combined with the characteristics and working principle of the cross-section flow velocity of the uniform flow in the open channel,the LED light is used to illuminate the tracer particles,and the narrow-band depth of field is used to obtain a clear velocity vector field pattern.After analysis,it is found that the measured results agree well with the theoretical formula,indicating that the technique has high accuracy and practicability in uniform flow regime.

关 键 词：粒子图像测速 LED光照 示踪粒子 明渠 均匀流 水平流速 

分 类 号：TV131.2[水利工程—水力学及河流动力学]