ON CALCULATION OF THE IRRIGATION PIPELINE PARAMETERS FOR DRIP IRRIGATION SYSTEMS OF GARDENS

Purpose: to study the dynamics of pressure losses in irrigation pipelines of drip irrigation systems and the associated uniformity of irrigation by emitters; to develop a technique for hydraulic calculation of irrigation network pipelines. Materials and methods. Field studies were conducted on the production site of an irrigated garden in the Neklinovsky district Rostov region. In the course of field studies of irrigation pipelines, the dynamics of pressure losses and the flow rate of emitters along the irrigation pipeline length were determined. Known methods and recommendations for hydraulic calculation of pipelines with variable flow rate were considered as an analytical base for the research. Results. At the production site, the significant uniformity of irrigation water supply from non-compensating emitters of the irrigation pipeline was determined: from 2.12 l/h in the initial section to 1.25 l/h in the end section, which is associated with a significant pressure drop: in the head section – 0.97 atm, in the end – 0.40 atm. The obtained results are explained by design deficiencies in substantiating the parameters of the irrigation pipeline. The analysis of the most well-known methods of hydraulic calculation of irrigation network pipelines revealed significant differences in the calculation results both in terms of methods among themselves and in their compliance with experimental data – from 10.4 to 30.4 %. As a result of the research, a method for hydraulic calculation of the irrigation pipeline has been developed, recommended for use in the following conditions: pipeline length from 20 to 200 m, pipeline diameter of 16–20 mm, emitter flow rate of 0.4–2.0 l/h, non-compensating emitter type, distance between emitters from 0.2 to 1.2 m, pressure in the head section of the irrigation pipeline of 0.8–2.5 atm. Conclusions. The proposed method allows establishing the irrigation pipeline length at which the pressure drop in it will not exceed the value that ensures the standard uniformity of irrigation water flow rate from the emitters.