Research On Monitoring And Evaluation Of Pipeline Sediment Concentration Based On Multi-Sensor

Sand production is almost inevitable during the process of production of oil or natural gas wells.Long-term high-speed sand-carrying flow erodes the elbow,which is easy to cause block pipes corrode and pipeline leakage.It even affects normal production,resulting in waste of resources and safety accidents.Therefore,the monitoring of pipeline sediment content has important practical significance,which is in line with the national carbon peak and neutrality targets.Among the common pipeline sediment monitoring methods,the acoustic monitoring method has the advantages of non-invasive,high sensitivity and long-term monitoring compared with the resistance monitoring method.Due to the complex fluid environment in the pipeline and external noise interference,the sensor perception is limited,the quantification accuracy is low,the particle size identification is difficult,and the environmental adaptability is poor.Therefore,how to realize sand identification and sand content quantification in pipeline gas-solid two-phase fluid in complex environment is the key to pipeline monitoring,which is the research topic of this thesis.Based on the physical model between the effect of solid particles on the wall and the erosion rate in the fluid erosion model,this master thesis proposes a multi-sensor signal physical erosion mapping method,and systematically studies the identification and quantitative evaluation techniques for monitoring solid particles.The research contents are as follows:(1)In view of the different monitoring characteristics of different sensors,this thesis proposes and solves the mathematical correlation model between sand characteristics and multi-sensor signals based on kinetic energy loss and multi-sensor fusion,combined with physical and sensing characteristics,the signal characteristics are used to analyze influencing factors of sediment monitoring,thus fully mine multi-sensing information.Aiming at the interaction between the gas-solid two-phase,solid particles and the pipe wall in the pipeline,the computational fluid dynamics is introduced to analyze the fluid erosion mechanism of the pipeline,and the factors affecting the erosion were analyzed and a new multi-sensor monitoring model of sediment content was established.(2)In order to monitor and identify sand particles and quantify sand content,according to the theoretical model proposed in(1),a directional frequency response acoustic emission sensor and a multi-sensor fusion sensor were designed and developed,and a pipeline sand content monitoring platform was designed and built.Based on the signal characteristics of the pipeline sand impacting the pipe wall,a directional frequency response acoustic emission sensor was customized,combined with vibration sensing as the sensing core,software system was completed after built of the monitoring platform.Experiments were designed to analyze multi-sensor signals to realize the functions of sand particle identification and sediment content quantification,and verify the mathematical feature model proposed in this thesis.(3)Aiming at the difficulty of sand particle size identification,the function verification of the pipeline sand content system was carried out through multi-sensor fusion training and platform establishment.In terms of sand particle identification,the time-frequency domain and statistical domain characteristics of multi-sensor signals were analyzed and compared,and the optimal position and identification influencing factors of sand particles were verified;in terms of sediment quantification,the effects and influencing factors of single and multi-sensor sediment quantification were evaluated.The experimental results verify the proposed mathematical characteristic model in this thesis,and show that the fusion of multi-sensor information can further reduce the monitoring error of sediment content,which provides research support for predicting the service life of pipelines.