Abstract
The authors of this paper have established an automatic water-discharge measurement system with a fixed type Non-Contact Current Meter (NCCM), especially Radio wave type. In the system, following three points must be discussed; 1) measurement of a representative flow velocity with the NCCM, 2) estimation of a velocity index, as well as 3) measurement of a river-bed fluctuation. In this paper, the authors mainly focused on the first point including the characteristics of water surface velocity, which were affected by wind and river-bed vibration. The water surface velocity obtained by NCCM indicates appropriate fluctuation cooperated with river-bed fluctuation. Comparing with ADCP measurement, the water surface exposed by the strong wind under-measured by NCCM which is needs to be corrected. The authors show the characteristics of those phenomena and introduce the wind-correction equation.
