Hydraulic Design of Pipeline of Right Bank Canal of Lendi Inter-State Irrigation Project, Maharashtra

Abstract

The hydraulic design of the pipeline is generally evaluated for its hydraulic functioning, which involves the assessment of passing the design discharge through it. It depends upon the adequacy of gross head and pipe diameter; precautions need to be taken to avoid water hammer in the pipeline, avoidance of negative pressure, avoidance of air-entrainment. The application of the energy equation shows that parameters such as discharge, pipe diameter, head loss, gross driving head, surface roughness of pipe are interdependent. Design period of the project and aging of the pipeline affect surface roughness and friction losses in the pipeline. The verification of the adequacy of diameter (for pipe with given flow rates, length of pipeline and available gross driving head) involves determination of friction factor with necessary allowance for ageing and calculation of head loss due to friction and form losses. Friction loss refers to fraction of pressure lost by flowing fluids through a pipeline. Form loss is due to the obstructions present in the line of flow, it may be due to change in alignment, may be due to a bend or a control valve or anything which changes the course of motion of the flowing fluid. Desk studies were conducted in CWPRS, Pune to assess hydraulic suitability of MS Pipeline of right bank main canal (Telangana canal), which is intended to divert 6.527 m³/s irrigation water to Telangana. From desk studies, it was found that, considering the roughness coefficient of epoxy enameled steel pipe line as 0.89 mm, the proposed diameter of pipe of 2 m and parallel pipes of 1.6 m each were found to be adequate to carry the design discharge with the available gross head of 16.25 m and the Project is under construction.