Sophistication of streamflow measurement method using an innovative underwater acoustic technique

2016 Fiscal Year Final Research Report

• Project/Area Number: 26289165
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Hydraulic engineering
• Research Institution: Hiroshima University
• Principal Investigator: Kawanisi Kiyosi 広島大学, 工学(系)研究科(研究院), 准教授 (40144878)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 河川流量 / 洪水 / 水資源 / 水循環 / 音響トモグラフィー法

Outline of Final Research Achievements

Acquiring streamflow estimates is crucial in hydrological studies, extreme event analyses and water resources management. This study demonstrates the improved fluvial acoustic tomography system (FATS), which are equipped with new GPS receivers that provide two accurate timing signals. The signal of 10 MHz, which has excellent long-term frequency accuracy and stability, is used as the base clock of FATS for high-precision transmitting/receiving signal processing. These improvements make the previous FATS more stable and allow the long-term running of the system. Streamflow measurements were performed in a mountainous river (mean depth: 0.8～2.5 m, width: 115 m) during 258 days. The results show the FATS enables us to collect reliable and accurate discharge data for long periods. Moreover, an array of acoustic stations is deployed and a depth-averaged flow velocity distribution pattern is continuously reconstructed using inversion schemes.

Free Research Field

土木工学