Study on transient migration characteristics of leaking bubble in gas well annulus
In order to study the effect of gas leakage on annular zone pressure,a prediction model of bubble transient migration was established based on the characteristics of gas migration in the gas well,considering buoyancy,gravity,viscous resistance,additional mass force,and Basset force.Based on the similarity principle,an experimental device for the transient migration of annular gas was designed to study the transient transport characteristics of gas under different injection volumes.The reliability of the bubble transient transport model was verified by the experimental results.Sensitivity analysis was carried out for the process of sustained casing pressure in typical gas wells.The results demonstrate that the key factors impacting bubble migration speed are bubble diameter,leakage pressure,temperature,and liquid density.The higher the bubble migration rate is,the shorter the sustained annular pressure recovery time is,and the annulus pressure of a gas well cannot be discharged in time,resulting in lower well safety.
gas wellsustained casing pressuregas leakagebubble migrationtransient migration
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维普
