A Study On Detection Technology And Assessment Methods Of Complex Long Pipeline

With the development of modern lines and pneumatic technology, the complex long pipeline indaily production and life is more important. Blocking which is in pipeline results in substantialeconomic loss and some safety incidents. However, the technology of complex long pipeline blockagedetection could not meet the needs of its obstruction detection because of its some defects. So it has astrong practical significance to study on assessment methods of characteristics and blocking detectiontechnology of the complex long pipeline. This paper use transient flow method to develop a blockagedetection technique, which is based on the study of the characteristic of the complex longpipeline.Details are as follows:（1） The theoretical analysis and simulation approach are used to assess the impact thepipeline chocked flow. The theoretical analysis is used to find out the velocitycharacteristics in chocked flow which is at the end of Simple pipeline and Variable diameterpipeline, and the condition of the pipeline flow generating congestion is evaluated;.Thesimulation method is used to verify the theoretical analysis, the flow characteristics ofcongested flow duct obstruction is Summarized.（2） Simulation Analysis is used to analyze the rule of the air flow pattern in blocking pipeline,and Pipe blockage traffic model is built. The simulation software FLUENT is used to studydifferent blocking factor of flow, and its flow effect which is on pipe is explored.A largenumber of simulation data are used to establish the blocking flow model.（3） The method of characteristics is used to establish duct obstruction detection model andcomplex long pipeline blockage detection method. Continuity and motion of partialdifferential equations of the pipe transient flow are deduced; the method of characteristics isused to derive the internal piping of each node pressure and flow iterative equation. Thepressure and flow model is proposed under the exhaust of constant volume which could beused to air flow before and after blocking. The rule of blocking flow is used to deduce theduct obstruction blocking.（4） The blocking detection device is used to verify the validity of the blocking detectionmodel which is based on the method of characteristics. The blocking detection device underthe exhaust of constant volume is designed and used to validity of the blocking detectionmodel which is established on the method of characteristics. Experiment proofs that theblocking detection model which is established on the method of characteristics could be used to detect the area of blocking in complex long pipeline, and the detection accuracy ishigh enough which can be a strong practical value.Results of this study have practical significance for the detection of complex long pipelineblockage, using constant volume deflated method of characteristics for the transient flow method inthe application of such a special pipeline has played a large role model.