Experimental Study On Acoustic Characteristics And Location Detecting Of Water Supply Pipeline Leak

In water supply network system,the pipeline leakage has been a very serious problem that human beings are facing.Therefore,the leak location detection has great practical application value.Water supply pipeline leakage detection method is numerous,and the acoustic detection applications is widely used.Background of this article is water supply pipeline leak,and use laboratory building water supply pipeline leak detection devices to collect leakage acoustic signal.Through the analysis of the signal,realize the water supply pipeline leak detection.The main research content is following:(1)Understand the basic theory of water supply pipeline leak location detecting.Use the spread of sound waves in the pipeline model and combine with cross-correlation analysis principle,deduces the basic formula of leak point positioning to provide theoretical basis for the leaking point positioning.(2)The changing rule of the leakage acoustic signal of water supply pipeline are analyzed under the condition of single factor,such as different pipes,pipe diameter,different connection methods,different pressure,different temperature and different medium temperature condition,the changing rule of the water supply pipe leakage acoustic signal,different pipe leakage acoustic characteristics have different influence factors,and the leakage acoustic signal frequency of steel pipe is greater than PE tube and UPVC pipe.Water pipe fittings such as elbow,tee have attenuation effect to signal.Also analyzed the changing rule of the leakage acoustic signal of the water supply pipeline under multi-factor interaction,the change rule of steel pipe leakage acoustic signal is affected by connection more than the medium temperature and the influence of medium temperature is bigger than the leak shape.(3)Combining with the wavelet transform can effectively distinguish the mutation part and noise signal,and improve the characteristics of the judgment of the leak signal characteristics.Fix the water supply pipeline leak detection,and reduce the leakage point positioning error.(4)Finally,the optimization method for different pipe leakage point positioning optimization model is established respectively,and select the genetic algorithm,theresults show that this method greatly reduced the water supply pipeline leak positioning error.After optimizing the steel pipe,PE pipe and UPVC pipe positioning error are reduced by 68.6%~96.4%,47.7%~57.1% and 18.3%~57.1%,and after optimizing,error of more than 0.5 meters are reduced to below 0.5 meters,can guarantee the accuracy of the pipeline maintenance excavation scope and repair timely.