河流水面成像测速方法的比测试验研究

大尺度粒子图像测速（LSPIV）是一种新兴的非接触式瞬时全场流速测量技术。以LSPIV为基本原理，针对现场条件下特有的水流示踪物、复杂的光学成像环境及受限的测点布设方式，通过对流场图像采集、水面背景抑制、运动矢量估计、时均流场重建、水面流场定标及断面流量估计等技术方法的集成创新，建立一套完整的河流水面成像测速（RSIV）工作模式。为评价RSIV的性能并提出研究需求，在现场开展与流速仪法和雷达法的比测试验。结果表明，RSIV法的时均流速测量精度可以达到0.5 mm/s以内，相比流速仪法具有更高的时空分辨率。当流速系数和断面划分方式选择合适时，流量估计值和雷达法的一致性较好。试验初步验证河流水面成像测速方法用于河流流速、流量测量的可行性。

Comparative Experiment Study on River Surface Imaging Velocimetry Method

Large Scale Image Velocimetry （LSPIV） is an emerging non-contact technique for measuring whole-field velocities instantaneously. Aiming at the specific flow tracers, complex optical environment and limited site deployment under field conditions, a complete operating mode of River Surface Imaging Velocimetry （RSIV） is built based on the fundamental principles of LSPIV and the integrated innovation of image acquisition, background suppression, motion vector estimation, time-average flow field reconstruction, flow field calibration and discharge estimation. To evaluate RSIV and propose research needs, comparative field experiments are conducted with current meter method and radar method. Results show that the accuracy of RSIV can achieve 0.5mm/s for time-averaged velocity measurement, the spatial-temporal resolution of which is higher than that of the current meter method. The estimated discharge is consistent with the measurement of radar method when choose the proper velocity coefficient and cross-section division. The experiment preliminary verified the feasibility of RSIV for river velocity and discharge measurement.