基于代表性垂线流速的在线流量测验方法研究

Research on online discharge measurement method based on representative vertical velocity

为提高流量在线测验精度,以长江下游干流八里江水文站为例,收集了八里江水文站2009~2021年84份流量测验成果,在分析测站特性的基础上,研究了该水文站流量测验断面平均流速与代表性垂线流速的关系,并计算了在线流量精度。结果表明:八里江水文站起点距为850 m和1 500 m的两条垂线平均流速与断面平均流速的确定性系数在0.97以上,推求流量不确定度为9.20%,满足一类水文站流量测验精度要求;起点距为850 m和1 500 m的两条测速垂线适宜作为V-ADCP自动测流设备安装位置。基于代表性垂线流速的在线流量测验方法可实现流速实时采集,提高流量测验精度并降低测验成本。

In order to improve the accuracy of online flow test,84 flow test results were collected from 2009 to 2021 at Balijiang Hydrological Station located at the main stream of the lower reaches of Yangtze River.Based on the analysis of the characteristics of the station,the relationship between the average velocity of the flow test section and the representative vertical velocity were studied.The results showed that deterministic coefficient between the average velocity of vertical lines with a starting distance of 850 m and 1500 m and the average velocity of cross section were above 0.97,and the flow uncertainty was 9.20%,which met the accuracy requirements of flow test of Class A station.The two vertical lines with a starting distance of 850 m and 1500 m were suitable for installation of V-ADCP automatic flow measurement equipment.The on-line flow measurement method based on representative vertical velocity can realize real-time flow velocity acquisition,improve the accuracy of flow measurement and reduce its cost.