Hydraulic Characteristics of Injection Flow Regulators

The effi ciency of the irrigation system can be increased by reducing unproductive water discharges from channels. Hydrodynamic fl ow regulators control water supply on demand and are activated when water consumption in the downstream of the structure is reduced below the design value. Many works have been devoted to the theoretical and experimental study of the hydraulic characteristics of the structures under consideration, but no universal dependence has yet been obtained for directly determining the amount of fl ow rates that merge in the regulator and the accuracy of water supply. The generally accepted scheme for merging fl ows in the regulator was the fl ow scheme in the exhaust tee, which later required making empirical corrections to align the theoretical dependencies with experimental data. In this paper, a fundamentally new approach to the calculation of hydrodynamic regulators is proposed – consideration of their operation as injection devices and the application of appropriate computational dependencies. The results of theoretical calculations are compared with the existing data of experimental study of several versions of the fl ow part of the regulators. The output section of all structures was made in the form of a pyramidal diffuser with a continuous fl ow. The fl ow coming from the upstream to the downstream was injecting, the fl ow circulating between the mixing chamber and the outlet section of the diffuser was injectable. Comparison of experimental data and the obtained theoretical curve showed a good match. As a result of the research, it was found out that the accuracy of regulation can be set by purposefully maintaining the necessary water horizon in the space above the diffuser and linking it with the amount of fl ow coming from the downstream through the spillway.