Transitórios hidráulicos como ferramenta de diagnóstico: estudo experimental e computacional de vazamentos em tubulações

Abstract

Water loss due to leaks is one of the main challenges faced by water supply systems, leading to significant economic and environmental impacts. Several techniques have been developed and improved over the past decades to mitigate this problem, with transient flow-based methods standing out as a promising alternative for leak detection. In this context, this study investigates the occurrence of leaks in water supply pipelines through the analysis of hydraulic transients, using experimental data and computational simulations in both the time and frequency domains. The main objective is to evaluate the ability of transients to detect leaks under different operating conditions, analyzing the influence of parameters such as leak magnitude and location, as well as the initial flow conditions. The methodology was structured into three main stages. A simplified computational model was developed to illustrate the behavior of transients and pressure waves. A representative model of the laboratory system was built to reproduce the experimental conditions. And experimental tests were carried out by varying the initial flow rate, leak size and position, and maneuver conditions, allowing direct comparison between numerical and laboratory results. The findings showed that the behavior of pressure waves is sensitive to both the magnitude and location of leaks, enabling the identification of characteristic patterns associated with different operating conditions. In the frequency domain, variations in the spectra were observed in relation to the presence and position of leaks, reinforcing the potential of spectral analysis as a complementary diagnostic tool. However, some limitations were identified. The differences between the computational and experimental models were mainly related to physical aspects of the laboratory setup, such as 180° bends and the position of sensors near the leak point. The adopted configuration also caused significant variations in the metrics and plots of sensors located close to the leak, reflecting local effects but reducing detection efficiency. The 180° bends increased the amplitude and dispersion in the experimental frequency spectra, highlighting the influence of pipeline geometry on wave propagation and reflection. Despite these constraints, the analyses yielded consistent results, providing a broader understanding of system behavior and contributing to the improvement of future modeling approaches and transient signal interpretation under real-world conditions.