ADCP流速及流量测量原理.ppt

1、,现代海洋测绘,PPT by 陈志高,ADCP流速及流量测量原理,2,声学多普勒流速剖面仪,Acoustic Doppler Current Profiler,起源：1980s 四大海洋观测仪器之一： 海洋 湖泊 河口,3,ADCP 是用于采集流速大小和方向的声学设备 流速剖面视为不同水层(Bin)或深度单元（Bepth Cell）的流速,基本概念,4,Acoustic Doppler Current Profiler,基本概念,5,声波发射,ADCP的换能器以固定频率向水体和水底分别发射一个短脉冲和长脉冲声波 声脉冲由于水里颗粒物存在反射并被换能器接收,6,声波发射,7,声波发射,ADCP收

2、到悬浮颗粒物反射回来的声波由于悬浮颗粒物的相对速度而产生频移 这就是多普勒效应,8,多普勒效应,Acoustic Doppler Current Profiler,9,多普勒频移,10,相对速度,悬浮颗粒物与换能器有相对运动才存在“多普勒效应” 如果悬浮颗粒物运动垂直于（90度）换能器则没有“多普勒效应” 知道了悬浮颗粒物与换能器发声方向的角度就可以通过“多普勒”频移推算出悬浮颗粒物的运动速度,11,相对速度, 8 Waves Measured,12,流速测量,Acoustic Doppler Current Profiler,13,流速测量,ADCP通常具有3个以上换能器，同时发射和接受3个

3、波束以上的声信号，获得3个以上的相对速度 信号按波束独立处理并转换成波束向相对速度 利用波速间的角度，将波束向（波束坐标）的相对速度转换为水平和垂向速度（地球坐标）,14,坐标关系和速度转换,波束坐标系：V1、V2、 V3、 V4,仪器坐标系：U、V、 W、 e,15,地球坐标系：,如果存在安装误差或罗经误差,坐标关系和速度转换,16,流速剖面,Acoustic Doppler Current Profiler,17,传统流速仪法,流速测量,流量测量,V流速（m/s） n 旋桨回转率，n=N/T(1/s) K 水力螺距（m） C为仪器常数（m/s）,流速面积法,实时 多垂线 多水深单元 效率高

4、 量程大,流速剖面,19,ADCP 测流回顾,Acoustic 以固定频率发射声波脉冲. Doppler 接受反射回来有“多普勒”频移的声波，通过频移计算波束向的相对速度 Current 应用4波速向相对速度、波速间夹角、姿态数据（首向heading,纵摇pitch,横摇roll） Profiler 测量不同层次（depth cell）的流速,20,走航式ADCP流速测量,21,盲区,上下盲区：,Distance = 3m,Depth,0.2,0.2,0.1,流量测量,Distance = 9m,Depth,流量测量,0.2,0.2,0.1,0.3,0.3,0.3,0.2,0.3,Distan

5、ce = 15m,Depth,流量测量,Distance = 21m,Depth,流量测量,0.2,0.2,0.1,0.3,0.3,0.3,0.2,0.3,0.4,0.4,0.5,0.4,0.5,0.4,0.3,0.3,0.2,0.3,0.5,0.6,0.7,0.6,0.6,0.6,0.5,0.5,0.4,0.4,0.3,0.3,0.2,Distance = 27m,Depth,流量测量,0.2,0.2,0.1,0.3,0.3,0.3,0.2,0.3,0.4,0.4,0.5,0.4,0.5,0.4,0.3,0.3,0.2,0.3,0.5,0.6,0.7,0.6,0.6,0.6,0.5,0.5,

6、0.4,0.4,0.3,0.3,0.2,0.8,0.8,0.8,0.8,0.7,0.7,0.5,0.5,0.4,0.4,0.3,0.3,0.2,Distance = 33m,Depth,流量测量,0.2,0.2,0.1,0.3,0.3,0.3,0.2,0.3,0.4,0.4,0.5,0.4,0.5,0.4,0.3,0.3,0.2,0.3,0.5,0.6,0.7,0.6,0.6,0.6,0.5,0.5,0.4,0.4,0.3,0.3,0.2,0.8,0.8,0.8,0.8,0.7,0.7,0.5,0.5,0.4,0.4,0.3,0.3,0.2,1.0,1.0,1.0,0.9,1.0,0.9,0.

7、7,0.7,0.5,0.5,0.4,0.4,0.2,0.2,Distance = 39m,Depth,流量测量,0.2,0.2,0.1,0.3,0.3,0.3,0.2,0.3,0.4,0.4,0.5,0.4,0.5,0.4,0.3,0.3,0.2,0.3,0.5,0.6,0.7,0.6,0.6,0.6,0.5,0.5,0.4,0.4,0.3,0.3,0.2,0.8,0.8,0.8,0.8,0.7,0.7,0.5,0.5,0.4,0.4,0.3,0.3,0.2,1.0,1.0,1.0,0.9,1.0,0.9,0.7,0.7,0.5,0.5,0.4,0.4,0.2,0.2,1.0,1.0,1.0,

8、0.9,1.0,0.9,0.7,0.7,0.5,0.5,0.4,0.4,0.2,0.2,Distance = 45m,Depth,流量测量,0.2,0.2,0.1,0.3,0.3,0.3,0.2,0.3,0.4,0.4,0.5,0.4,0.5,0.4,0.3,0.3,0.2,0.3,0.5,0.6,0.7,0.6,0.6,0.6,0.5,0.5,0.4,0.4,0.3,0.3,0.2,0.8,0.8,0.8,0.8,0.7,0.7,0.5,0.5,0.4,0.4,0.3,0.3,0.2,1.0,1.0,1.0,0.9,1.0,0.9,0.7,0.7,0.5,0.5,0.4,0.4,0.2,0.

9、2,1.0,1.0,1.0,0.9,1.0,0.9,0.7,0.7,0.5,0.5,0.4,0.4,0.2,0.2,0.9,0.8,0.8,0.6,0.5,0.4,0.2,0.8,0.8,0.7,0.5,0.4,Distance = 51m,流量测量,0.2,0.2,0.1,0.3,0.3,0.3,0.2,0.3,0.4,0.4,0.5,0.4,0.5,0.4,0.3,0.3,0.2,0.3,0.5,0.6,0.7,0.6,0.6,0.6,0.5,0.5,0.4,0.4,0.3,0.3,0.2,0.8,0.8,0.8,0.8,0.7,0.7,0.5,0.5,0.4,0.4,0.3,0.3,0.

10、2,1.0,1.0,1.0,0.9,1.0,0.9,0.7,0.7,0.5,0.5,0.4,0.4,0.2,0.2,1.0,1.0,1.0,0.9,1.0,0.9,0.7,0.7,0.5,0.5,0.4,0.4,0.2,0.2,0.9,0.8,0.8,0.6,0.5,0.4,0.2,0.8,0.8,0.7,0.5,0.4,0.7,0.7,0.6,0.4,0.3,0.6,0.4,0.3,0.2,Distance = 57m,流量测量,0.2,0.2,0.1,0.3,0.3,0.3,0.2,0.3,0.4,0.4,0.5,0.4,0.5,0.4,0.3,0.3,0.2,0.3,0.5,0.6,0.7,0.6,0.6,0.6,0.5,0.5,0.4,0.4,0.3,0.3,0.2,0.8,0.8,0.8,0.8,0.7,0.7,0.5,0.5,0.4,0.4,0.3,0.3,0.2,1.0,1.0,1.0,0.9,1.0,0.9,0.7,0.7,0.5,0.5,0.4,0.4,0.2,0.2,1.0,1.0,1.0,0.9,1.0,0.9,0.7,0.7,0.5,0.5