利用micro-PIV测量矩形微管道内流量

摘要

利用微观粒子图像测速技术(micro-PIV)测量了矩形微管道内低雷诺数下速度矢量场,并以此为基础计算微管道内流体体积流量.微管道水力直径为83μm,横截面深宽比为0.155,长度为17mm.实验中获得雷诺数分别为47、127和215三工况下管道中心水平截面内速度分布.与理论速度剖面比较,管道中心的测量速度值吻合很好,偏差控制在±2%以内.利用中心速度值结合层流解析解计算微管道内平均流速和体积流量.经过误差分析得到该方法测量误差约为3.3%.实验结果表明,利用micro-PIV技术完全可以实现微通道流量的高精度测量.%The velocity fields in a rectangular microchannel were obtained by micro particle image velocimetry (micro-PIV), with low Reynolds numbers. Based on the measurment of velocity fields, the flow rate was calculated. The microchannel was 17mm long with a hydraulic diameter 83tm and the aspect ratio of the microchannel cross-section was 0. 155. The horizontal volocity fields on middle plane under Renolds number of 47,127 and 215 were gained. The results show that the measured velocity data were consistent with the theoretical velocity profiles in the middle region, and the deflection was within ±2％. The mean velocity and volumn flow were calculated with the center velocity data and the fornula of laminar flow in rectangular duct. The measurement errro was 3.3％ approximately. The experimental results show that high accurate flow rate measurement can be realized by micro-PIV techniques.