Analysis of the smallest detectable leakage flow rate of negative pressure wave-based leak detection systems for liquid pipelines

One of the most concerned performance indices of leak detection and location systems is the smallest detectable leakage flow rate (SDLFR). Based on the physical model of pipeline, mathematical description for the amplitude change of negative pressure wave (NPW) and its attenuation traveling along the pipeline have been deduced. On the basis of mathematical description, the methods for evaluating SDLFR and determining the sensitive point of the pipeline have been proposed. Further study shows that factors such as leakage position, pressures at inlet and outlet, flow rate, density, wave speed in the pipeline, precision of the instruments and noise will have influences on SDLFR. And the results are of great significance to evaluate the performance of the systems based on NPW method.