|Welcome to River, Estuarine and Coastal Engineering, Hiroshima University.
Streamflow is an important hydrological factor in river and coastal planning/management,
control of water resources, and environment conservation. Therefore, it
is a key issue to establish the measurement method and subsequent technology
for measuring stream flow.
Fluvial Acoustic Tomography (FAT) system, which is developed by my research group in Hiroshima University, has
a few noticeable functions represented by the accurate measurement of travel
time using a GPS clock and the attainment of high signal-to-noise ratio
as a result of transmission signal modulation by the 10th order M-sequence.
As shown in the above aerial photo, a couple of transducers of central
frequency of 30 kHz are installed diagonally across a river.
Example of an estuarine cross-section: contour plot of sound speed distribution
and a result of ray simulation (ray pattern).
The cross-sectional average velocity of the river stream can be estimated
from the travel time difference data, obtained along the ray paths that
cover the channel cross-section.