Influência de manobras de válvulas na identificação da rugosidade de tubulações em redes hidráulicas com dados transientes

Abstract

In view of the increasing complexity of the hydraulic networks present in large urban centers, simplistic analyzes of the physical phenomenon that occurs inside the pipes can generate several problems. The first one is the undersizing of the system for possible increases and decreases in pressures inside the ducts caused by the hydraulic transient. Another neglected point is the quality of the calibration of the fundamental parameters of the system, such as the pipes’ absolute roughness, a fact that can lead to a lower performance of the system than expected. In this context, in order to make the analysis more reliable, the process as a whole becomes much more complex, requiring new approaches to solve sizing and calibration problems. One of them is the Inverse Transient Method combined with a genetic algorithm (ITM-GA), which allows the resolution of the inverse problem found in hydraulic networks whose parameters are unknown. Based on concepts such as hydraulic transient, Method of Characteristics, optimization and calibration, it is possible to bypass the complexity imposed by a problem with such characteristics. Thus, this study seeks to better understand how the valves maneuvers influence, which are many times responsible for the occurrence of the ‘hydraulic transient, in the calibration process of the absolute roughness parameter using the ITM-GA. In this perspective, it was noticed that, for the maneuvers and the networks analyzed, the calibrations’ results differ depending on the sealing speed of the valve and the size of the network. However, it is not possible, based on this study, to state categoically which maneuver is the most appropriated for a given situation, since others simulation involving several other types of valves maneuvers and hydraulic networks must be done, in order to perceive and stablish result patterns.