Sub-theme
2. Promoting Water Efficiency, Productivity and Services
Topic
2-1. Water supply and demand management
Body
Box-shaped Ultrasonic Flow Meter for Open Channel (hereinafter Meter Box) is a box-shaped flow meter for open channel volume measurement. It employs ultrasonic time-difference technology to determine velocity by measuring the transmit time taken for the pulses travelling between transducers. The quantity of transducers is varied from 8 to 24 pairs according to the size of meter box. The purpose of designing meter box is to increase the irrigation water measurement accuracy and provide reliable flow rate data to water management authorities. To achieve that, meter box needs to perform under many challenging conditions like turbulence, changeable distribution area, and even sedimentation occurred in the channel. Transducers are allocated across four side panels in split level within meter box. Multiple ultrasonic array in split level maps the velocity profile that enables the flow meter to be resistant to swirl, or other unstable flow configuration. The flow transducers can not only provide multiple transecting paths, but also reflect the sedimentation height caused by mud and sand in the flow. Optimized the data from electric draught, ultrasonic water level gauge and transducers provide the true water depth in the box, alone with the interior width of the flow meter, meter box calculates the water distribution area, which secures the measurement accuracy when the meter box is partially full in the field. Independent verification of meter box’s measurement accuracy in the laboratory and in the field under a wide range of conditions. Factory calibrated each flow meter sold on at least three different water levels, within flow measurement accuracy of ±2%. No requirement of calibration or configuration on site. Accuracy of ±2% in accordance with T/CIDA 0007-2021 verified by National Test Center for Equipment of Irrigation and Drainage, with the reference meter from Germany KROHNE Magmaster. Integrated design allows easy installation on site. Energy supply and data collection through one RS485 cable. Low power consumption allows remote reading module and batteries to be integrated into the top panel of the meter box. Wide application from north-west to the South area in China, reliable flow rate data source to help local authorities to improve water resource management efficiency. Comparing to existing flow measuring devices, which provide velocity of single path in the water or single point on water surface, meter box promise much more accuracy by maping the whole velocity profile of the distrution area. The volume of installation in the field exceeds three thousand units.