Reliable and convenient discharge metering in rivers, streams and canals

Nivus’ new NivuFlow Stick mobile measurement system enables an accurate and complete measurement of an inland waterway’s flow profile. The system was designed for use in flow levels lower than 75 cm where Acoustic Doppler Current Profiler (ADCP) floats reach their limits of effectiveness and classic methods of using a wading rod come into play. With the aid of an integrated hydrostatic level measurement, the shape of the river bed is determined right while the measurement is in process. NivuFlow Stick directly computes the discharge rate and represents it graphically. In contrast to propeller-type current meters, which can capture flow velocities only point by point, the velocities here are measured from the bottom to the surface simultaneously and seamlessly. Laborious positioning works in different measurement depths are no longer required.
The new measurement system takes negative velocities as well as hydraulic disturbances into account. Using the standard 1-, 2- or 3-point calculation method according to ISO 748 such disturbances lead to considerable inaccuracies which often remain undetected. Thanks to the NivuFlow Stick such deviations from the theoretic flow profile become immediately evident and are already considered in the calculation.
Easy handling enables even untrained users to reliably use the measurement system very quickly and perfectly. After specifying width and number of sections the unit indicates the individual measurement positions directly so that users only need to execute the measurement at the corresponding position. Once the adjustable measurement duration has expired the metering process is terminated automatically and the next position is indicated. Red and green signals give clear indication on the quality of measured data already during the measurement process.
NivuFlow Stick is operated by using the web browser of a smartphone or other mobile device. There is no need to install separate software applications. The capacity of the internal memory is up to 1400 discharge measurements.
The NivuFlow Stick is operated with standard rechargeable AA-size batteries which can be quickly and easily replaced by users if required. Moreover, the system fits easily into any car without the need for disassembly. The system contains no wearing parts and is maintenance-free.
Previous measurements can be loaded and visualised again. Deviations in measurement quality are indicated by the system and are identified in the saved data. The system provides data output in various file formats, for example as a complete PDF measurement report which, besides readings and metadata, also includes the graphic representation of the measured flow profile. Nivus will be exhibiting at the upcoming IFAT trade fair in Munich (Hall 1 Stand 251/350).