Ultrasonic methods and instruments for measuring water flow in hydroreclamation systems
Purpose: analysis of existing ultrasonic methods and devices for metering water flow in irrigation and drainage systems. The problem of rational use of water resources exists in all areas, including agriculture. It cannot be resolved without considering the issue of water metering and water distribution. The main task of the water accounting system in irrigation and drainage systems is measuring the volume of water taken from the water intake and delovered to the irrigation network. For these purposes, flow meters - devices that measure the flow of water, are used. Ultrasonic (acoustic) flow meters are flow meters capable of solving complex problems in flow measurement. Currently, there are several measurement methods to determine the water flow rate at reclamation facilities: ultrasonic, radar, Doppler method, cross-correlation method and Transit-Time method. Based on these methods, a large number of modifications of devices for determining water flow rates have been created: level gauges, radar flow meters, Doppler flow meters, submersible cross-correlation flow meters, pulse-time flow meters. Conclusions. Flow meters based on level gauges and radar flow meters are impractical to use in commercial water metering units. They have high flow measurement errors, since level gauges measure only the level, and the speed is taken as a constant value, while radar flow meters measure the flow rate, but this is not the speed of the entire flow, but only of the surface layer. The flow rate measured by Doppler and cross-correlation meters depends on the amount of solids in the flow. But since the water in canals and closed pipelines on irrigation and drainage systems has a large number of solids, these flow meters have a high accuracy of flow measurement. Pulse time meters, as well as Doppler and cross-correlation meters, have high measurement accuracy, but do not depend on the amount of solids in the flow.