Prediction of Flow Variation of Downhole Throttling in Condensate Gas Wells and Its Applications

In allusion to the problem of characters of physical parameter changes and not deeply understanding the selection of working systems after throttling,combined with the characteristics of the downhole throttling and physical parameter models for two phase flow,a variation of the flow patterns before and after throttling was predicted and studied.The results indicate that obvious retrograde vaporization would be induced in condensate gas after throttling,and simultaneously the drawdown of the pressure would result in rapid gas expansion and an increase in gas flow velocity, the difference between the gas velocity and the critical liquid carrying velocity after throttling is larger than that before downhole throttling,which also indicates that liquid carrying capacity is improved after downhole throttling.The variation tendency of the physical parameters before and after downhole throttling is clarified through variation prediction in the downhole flow patterm of the gas condensate wells,and it provides reference for the design of downhole throttling techniques of similar condensate gas wells.