Evaluation of Influence of Hydraulic Transient Phenomenon on the Flow of the Main Pipeline of Moamba Village Water Supply System

The water supply system (SAA) in the Moamba village has suffered frequent leaks and ruptures in the main pipeline, compromising the activities of users as well as losses to the system. The aim of this study was to assess the influence of hydraulic transient (HT) phenomenon on the flow of the main water main in Moamba village water supply system. The following parameters were checked: (i) physical parameters in terms of Nodes (N), by length of each connection; stretches, by defining the pipe wall, internal diameter, celerity and suction cups; and (ii) the profile of the raw water pipeline, through manual excavation, water supply time in working hours, and checking the operation of the pumps, with the aim of analyzing the pressures acting on the system. Simulations were carried out using Allievi software. The results of the physical parameters showed celerity with maximum pressures in the permanent regime at the inlet of the pipe of around 97.64mca, and a minimum of 5.50mca at the outlet; no HT, the overpressures were close to the pressure line in relation to the permanent regime, however, there was a single case of -21.08mca representing a risk to the pipe. As a solution, suction cups, pressure regulating valves and hydropneumatic reservoirs were tested, which proved to be effective in smoothing out the pressure envelopes, but did not solve the problem of underpressures operating below the water vapor pressure.