Study On Leak Detection Of Water Supply Pipeline

The shortage of water resources in China is very serious,which absorbed a large amount of financial and material resources.However,the utilization rate of water resource is very low in our country and pipeline leakage exists widely.In daily life,only a large area of water leakage caused by pipeline leakage,can we discover the leakage.If the leak can be detected in time,the necessary measures can be taken to reduce unnecessary losses and it will save a lot of water resources.Therefore,it is not only of great theoretical significance but also of great practical value to study the leakage detection methods of water supply pipeline.In this paper,the signal analysis and processing technology of pipeline leak detection is studied,which improves the detection accuracy of leakage signal.The signal to noise ratio(SNR)of the signal obtained from the sensors installed on the outside of the pipeline is very low,which will seriously affect the accuracy of the leak detection.Therefore,through the analysis of the mechanism of the leakage signal,firstly,the study of the method to enhance the water leakage signal is studied.After reducing the noise,the leakage signal detection method has been improved and studied.The specific contents of the thesis include:Using the sensor to collect the vibration signal of pipeline leakage,the time domain and frequency domain characteristics of the leakage signal and noise signal are analyzed.? By using the sensor to collect the vibration signal of pipeline leakage,the time domain and frequency domain characteristics of the leakage signal and noise signal are analyzed.? In this paper,a new denoising method is proposed based on the characteristics of noise signal in pipeline leakage signal.Signal enhancement method based on spectral subtraction and wavelet denoising.Firstly,the effect of pipeline vibration is eliminated by spectral subtraction,and then the influence of environmental noise on leakage detection is reduced by wavelet threshold denoising.? The traditional method of pipeline leak detection based on signal characteristics is simulated,and the effects of different methods are compared under different SNR conditions.On the basis of summarizing the characteristics of each leak detection method,a new detection algorithm based on multiple features and neural network is proposed.The characteristics of short-time energy,short-time zero crossing rate and spectral variance are extracted as the input of BP neural network,and then the leakage signal can be detected in the trained neural network.? Leak signal enhancement method based on spectral subtraction and wavelet denoising and leakage signal detection method based on signal feature and neural network are applied to the actual water supply pipeline leak detection.The results show that the two methods can be used to detect the leakage signal correctly and effectively.