Research On The Law Of Water Hammer Duration When Pump Starts And Its Application In Pipeline Leakage Detection

The core equipment of the petroleum pipeline transportation is the pipeline and the power unit,as a whole,it can be regarded as a chain production equipment.Through the monitoring system installed on the pipeline,the water hammer can be observed in different positions.Water hammer,as an objective phenomenon,has its generation,propagation and degradation processes,which are embodied in many dimensions,such as energy,time and space.It can be known that the current research on water hammer is mainly concentrated in the energy dimension,and there is little research on it from time and space dimensions.But the change of water hammer in the form of time and space often affect the stability of the pipeline monitoring system based on the function of the data platform.Therefore,based on the understanding of the water hammer in the pipe,this paper studies the negative pressure water hammer and the positive pressure water hammer produced by the pump starts.(1)Study on the design scheme of water hammer duration of long oil pipelineThe extraction method of water hammer's duration is proposed firstly in this paper through the analysis of water hammer wave;the mathematical model of water hammer's duration is assumed which is influenced by the situation of pipeline and pump,fluid physical parameters.Then the data set is obtained through the SPS simulation software under different parameter combinations of pipe length,diameter,pump lift,fluid density and viscosity index,which is applied to simplify and solve the mathematical model.(2)Study on duration of water hammer when pump startups in long oil pipelineAssuming the mathematical mode of PWHDT and NWHDT after starting 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.These models can calculate the duration time of water hammer after operation of starting pump.(3)Study on the fusion rule of multiple water hammers in long oil pipelineFrom the time dimension,research on the behavior characteristics of the water hammer fusion has engineering application value.The analysis of water hammer duration's time features is founded firstly in this paper.Then using interval analysis theory,define the representation of water hammer interval;propose the fusion rules and calculation steps of multi water hammer duration intervals.(4)Research on pipeline leak detection based on duration of water hammerApplying the fusion law of water hammer durations to the conventional negative-pressure wave leakage detection system,propose a method for eliminating false alarms and describe the specific application steps.The experiment results prove that this false alarms excluding method is effective and easy to use.