Study On Performance Of The Steam Ejector Used For Low Pressure Gas Well Deliquification

At present,traditional deliquification technology is not suitable for low-pressure gas wells.In this thesis,a new type of ejector deliquification technology was proposed to solve this problem.High-pressure gas was used as a driving fluid to prevent secondary contamination.The problem of low efficiency was solved by forming a composite process with the foam scrubbing,and the ejector is the core of the technology.The aim of this study was to investigate the ejector flow characteristics for gas flow field and gas-liquid flow field by Computational Fluid Dynamics(CFD),the entrainment ratio was selected as the performance index,and the influence of ejector structure size and operation condition was obtained.The results showed as followed:For gas flow field,divergent taper and area ratio was the single peak trend in a certain range,the entrainment ratio will drop sharply when divergent taper increases to a certain extent,area ratio will not lead this change.The increase of nozzle distance can enhance the entrainment ratio.For gas flow field,operating condition have an impact on shock wave intensity and ejector running state.the increase of working pressure and decrease of outlet pressure enhance entrainment ratio and cause the chocked condition occurrence.For gas-liquid flow field,the effect of operating conditions on the ejector performance was basically the same as that of the gas flow field.The working pressure affected the ejector performance by changing the shock wave intensity.The outlet pressure affected the ejector performance by changing the jet core size.