Experiments on Determination of Water Consumption in Case of Free Flow under Gates in Irrigation Networks

Abstract

Efficient use of water resources and their accurate accounting are among the most important tasks in irrigation networks. In particular, accurate measurement of water flow through gates (sluices) in water distribution on the scale of irrigated fields remains an urgent problem. In this regard, determining the flow coefficient (μ) when water flows freely under the gate is of great importance. Since μ varies depending on the variable hydraulic parameters such as the gate opening height (h), the water level in the upper reaches (H), the compressibility, and velocity coefficients. Although μ is given in the literature in a number of intermediate values, it has been found that using it as a constant number in field and laboratory tests leads to significant errors. The main hydraulic parameters of the flow under the gates were determined in laboratory conditions, taking into account different opening heights (h) and head at the upstream (H). Then, the experiments were re-checked in field conditions and compared with the available hydro post data. As a result, a method for determining μ was developed to determine the water flow at any opening height (i.e., when the ratio α/H is different). This method provides high accuracy in determining the water flow compared to other similar formulas. The study also introduced digital technologies, and a mobile application for smartphones was created. This mobile application allows you to quickly determine the value of μ and calculate water consumption based on the gate opening height and upstream water flow. By entering the gate width (b), opening height (h), and H values, you can get results within seconds. Thus, the water distribution process will be faster, less expensive, and a fair relationship between farmers and water authorities will be ensured.