Research On The Influence Law Of Water Hammer Duration Time In Pipeline Leakage Detection

Pipeline is the most important equipment in the oil pipeline transportation system,the consequences are serious when happened leakage accident.The method of negative pressure based on recognition the single waveform of leakage which to judge the leakage,but in the field of production,the normal operating also can produce negative pressure,which cause the system false alarm.Through analysis the loacal data of false alarm,found that 50% false alarm comes from the operation of stopping pump,so the object of research is water hammer duration time of stopping pump in this paper,depending on the projects of National Natural Science Foundation of China “Multisource information fusion model of degradation system in pipeline leakage detection”(51204203)and Fundamental Research Funds for the Central Universities(14CX02134A),carry out the research on the influence law of water hammer duration time in pipeline leakage detection.(1)Model building of long distance pipeline using SPS softwareDetermine the scope of parameters change of SPS simulation model and simulation interval,establish the SPS standard model to obtain the data.Obtaining the waveform of water hammer at different monitoring points of pipeline after stopping pump,which similar to leak waveform.The discriminant method of pump water hammer duration is proposed.(2)Research on the formation law of stopping-pump PWHDT?NWHDT in long distance pipelineAssuming the mathematical mode of PWHDT and NWHDT after stopping pump,combination method of single factor sensitivity analysis and local sensitivity analysis,to determine the sensitivity of the various parameters in the model,and simplified the mathematical mode,through the data verification,the accuracy is proved.This model can calculate the duration time of water hammer of pump outlet after operation of stoping pump.(3)Research on the propagation law of stopping-pump PWHDT?NWHDT in long distance pipelineSpecific to the the spread of the water hammer in pipeline degradation phenomenon,define the attenuation coefficient,through analysis the reasons for degradationand combined with field data,established the mathematical mode of attenuation coefficient,byexperimental verification and error analysis,proved its meet the engineering requirements.This model can predict the water hammer duration time at different monitoring points.(4)Research on the method of pipeline leak monitoring of long distance oil pipeline based on the influence law of stopping pump water hammer duration timeFor the problem of fault alarm in pipeline detection,put forward a kind of pipeline leak detection method based on the influence law of water hammer duration time after stopping pump.It adopts the pipeline pressure abnormal capture algorithm based on volatility,improve the capture ability of abnormal pressure.As the core of mathematical model of PWHDT and NWHDT after stopping pump,to establish the fault alarm elimination model of pipeline leakage monitoring,combining it with the negative pressure wave leak detection method can solve the problem of high fault alarm rate.