Author(s): Yuya Suzuki; Jin Kashiwada; Yasuo Nihei; Tomohito Fujii; Kenji Taira; Elii Ueda; Junya Kaji; Ichiro Fujita
Linked Author(s): Ichiro FUJITA
Keywords: River discharge; STIV; DIEX method; WDIC; Long-term monitoring
Abstract: Monitoring river discharge is important and necessary to manage the river. However current methods for the river discharge monitoring have a lot of difficulty in the aspects of measurement accuracy and safety. In this study, we propose a new monitoring method by using an image processing and numerical analysis to solve such issues. In this system, we use a CCTV (closed-circuit television) camera to record the water surface in river and analysis the lateral distribution of surface velocity by using Space-Time Image Velocimetry (STIV) developed by Fujita et al. (2007). Then we calculate river discharge from measured velocities at discrete points in cross-sections by using Dynamic Interpolation and EXtrapolation (DIEX) method presented by Nihei and Kimizu (2008). We conducted a long-term monitoring for river discharge in the Onga River in Fukuoka Prefecture, Japan. Furthermore, laboratory experiments with an open channel are conducted to confirm the validity of STIV under various wind conditions. The results of field measurements indicated that the present system has been succeeded automatic and continuous discharge monitoring for nine months. It is also noted that the calculated discharges in the present system were almost good agreement with the observed data by ADCP. The results of laboratory test show that the measured velocities with STIV were comparable to reference data by floats under favorite and adverse wind conditions.
Year: 2018