Results of hydraulic calculations of the Chernozemelskaya irrigation system channels

Abstract

Purpose: hydraulic calculations of the current water supply network of the Chernozemelskaya irrigation system channels. Materials and methods. The materials for the calculations were: operational records of the Chernozemelskaya irrigation system, the results of field surveys of channels and data from instrumental measurements of water levels, velocities and water discharges in the surveyed discharge section lines of distributary channels. The field work was carried out according to the generally accepted rules and methods of surveys, hydrometric measurements and assessment of the reclamation facilities state. Channel hydraulic calculations were performed for the conditions of constant water flow in their channels on rectilinear sections. Calculations of the main elements of the water cross-section of the Chernozemelskaya irrigation system channels were carried out using passport data and the results of field surveys of these channels. Results. Calculations of the main elements of the water cross-section of the channels for the control stations on the Yashkul and Gashun distribution canals of the Chernozemelskaya irrigation system were performed, rating curves of discharge and average water flow velocity in channels from the depth of their filling were constructed; permissible (non-eroding and non-silting) velocities of water flow in the channels were determined. Conclusions. It was found for the discharge section line on the Gashun distribution canal, that siltation of the channel will occur at a water flow discharge of Q < 2.75 m³/s and channel filling of h < 1.0 m. When assessing the channel of the Gashun canal for the susceptibility to erosion, it was determined that the channel in the control station section can pass the specified discharge without being eroded. Checking the channel of the Yashkul distribution canal in the control section for siltation and erosion showed that its channel will not be eroded in the considered range of water flow velocities from 0.62–1.14 m/s.

Keywords

• irrigation channel
• channel
• hydraulic calculation
• discharge
• non-eroding velocity
• non-silting velocity