The purpose of this study is the hydraulic calculation of head losses (potential energy) along the length and in local resistances of the closed self-pumped distribution network of the fifth stage of the Great Stavropol Canal, which makes it possible to select the optimal pipeline diameters, corresponding to their calculated and maximum discharge at permissible water velocity. The hydraulic dependences for calculating the individual elements of the closed irrigation network are given, taking into account the energy loss (head) of the flow at each section of the linear scheme, where the mutual position of all pipelines and sprinklers connection points are shown. The method of investigation was the application of theoretical material using the Daniel Bernoulli equation to determine the energy loss (head) of water flow when used by irrigation machines, analyzing water discharge at the points of outlets, etc. Hydraulic calculation was performed according to the developed algorithm. The information on the condition of target of research was obtained with the use of modern means of data communication. The materials used were large-scale topographic maps, a developed digital relief model, longitudinal profiles, as well as programs to process the data. A one-dimensional hydraulic model of the distribution irrigation network is constructed. An imitating model of the irrigation system of the fifth stage of the Great Stavropol Canal has been developed, and hydraulic characteristics for each of its elements have been determined. A perspective route (linear scheme) of a closed self-supporting water conduit of a diversion irrigation network with a maximum length of 61.7 km with 13 proposed inter-farm distributors is planned.
Key words: distribution irrigation system, irrigation system elements, hydraulic structures unit, hydraulic calculation, linear losses, local pressure losses.
