Study On Mechanical Behavior Of Injection And Production Pipe String In Underground Gas Storage

In recent years,with the rapid increase in natural gas demand in China,natural gas regulation and control has become an important means to balance the energy inequality in the east and west.Underground gas storage is an important member of the peaking system because of its advantages.The injection and production of the column is connected to the underground reservoir and the overground pipe network to ensure that the high pressure injection under the safe operation of the important components of the well.In this paper,the mechanical behavior of the injection column is studied in the process of the operation of the gas storage wells.The following four aspects are carried out:First of all,through the analysis of the fluid migration mechanism in the injection column,the basic properties of the gas in the column and the theoretical description of the motion equation are emphasized.Based on ANSYS Workbench,the flow field analysis model of underground gas storage is established.Based on the analysis of the whole well,the flow field and the effect of fluid on the column are studied.The influence of different influencing factors on the pressure of the pipe wall of the oblique section and the packer section provides a theoretical basis for the vibration and buckling analysis of the column.Secondly,based on the theoretical analysis of the modal and vibration forms of the injection pipe,combined with the results of the flow field analysis,the finite element model of the injection pipe is established by software,and the influence of different factors on the shape of the pipe string is analyzed.Based on the analysis of prestressing mode,the transient dynamics analysis and multi-cycle harmonic response analysis were carried out to study the stress and vibration law of the column during the initial stage and steady-state operation stage.The influence of different factors on the vibration of the string is studied.In order to further describe the behavior of the injection pipe in the well,the buckling problem of the constrained tubing string is analyzed from the differential equation and the critical load.The ABAQUS software is used to establish the buckling model.The influence of different factors on the buckling of the string is studied,and the buckling behavior of the column is analyzed.Finally,the design of the injection column is analyzed from three aspects: stem optimization,strength design and sealing design.Combined with the flow field analysis,vibration analysis and buckling analysis,the use of Visual Basic language,the commercial software FLUENT,ANSYS and ABAQUS secondary development,the preparation of more easily on-site application of "Study on Mechanics of Injection and Production Pipe String in Underground Gas Storage V1.0"...