【摘要】 在基于颗粒示踪和图像处理方法的流场实时测量中,示踪颗粒的性能对流速测量的精度影响很大.为此,设计了一种半球形带沿的颗粒,其淹没深度较小,可以适用于较浅的水流条件,并通过试验研究了其分散性和跟随性.从试验结果可以看出,这种颗粒在运动过程中基本不会聚积成团,其运动速度达到稳定的时间和水流流速大致成对数曲线关系.示踪球的稳定速度和碎纸屑基本一样,可以认为这种颗粒能代表当地水流的运动速度.更多还原

【Abstract】 The properties of the particle have a significant impact on the precision of velocity measured in real-time velocity field mea-surement with the Particle Tracking Velocimetry approach and Image Processing Technique.A semi-spheric particle with border is devel-oped.Because it has a small submersed depth,it can be used in shallow water.The properties of the particles are studied by experiments.The particles of this kind almost never aggregate to form masses,and the accelerating time conforms to the log law with the speed of the water.The speed of the paper slip and that of the particle after acceleration under the same water conditions are measured.As can be seen,the speed of the particle is almost the same as that of the paper slip.It can be assumed that the speed is a good representation of the speed of the water at the spot.更多还原