| Abstrakt: |
Hydrodynamic as well as balance analysis of flow or discharge conditions in surface streams cannot be done without knowledge of the basic hydraulic parameters of the flow. These are, for example, the bathymetry of the water body, the distribution of velocities in the transverse and longitudinal directions, roughness, etc. To determine the value of discharge in a given cross section profile, it is necessary to know the discharge area and the velocity profile. There are several devices and methods for measuring these quantities. Recently, devices based on the application of the Doppler principle are increasingly being used to determine velocity profiles and discharges in field conditions. In ideal conditions, the use of such devices is very effective, but in the case of the presence of aquatic vegetation below the water surface, a problem may arise. The paper analyses the accuracy of determining the discharge area in a lowland stream with a small longitudinal slope with the presence of aquatic vegetation using the Acoustic Doppler Current Profiler (ADCP) device (River Surveyor, SonTek/a Xylem brand). The results of the analysis show that for such cases, this method shows limitations, the extent of which depends on the used sub-method (Bottom Track or Vertical Beam), as well as on the amount of aquatic vegetation below the water surface. [ABSTRACT FROM AUTHOR] |
