Ultrasonic Streamflow Monitoring System
In this study, we developed a system of continuous accurate monitoring of streamflow, which is composed of a pair of ultrasonic Doppler velocity sensors installed on an existing low head broadcrested agricultural small dam. In case of using this dam, errors in computing area are minimized due to stability of it, so that discharge can be accurately measured. In addition, by direct measurement of velocity over dam crest, this system can measure discharge not only for modular flow in which free fall occurs, but also for submerged flow affected by downstream as far as depth and velocity are measured. Preliminary results for 15 dam release events display that discharge obtained by this system is in quite good agreement with dam release and with H-Q relationship. Comparison of volumetric discharge is also made and relative difference with dam discharge is 2.7%.
