A calculation model for critical liquid-carrying flow rate of shale gas horizontal well section
Full lifecycle gas-liquid co-production is an important feature in shale gas well production,and wellbore liquid loading is a key factor affecting well production in the middle and later stages.The traditional calculation model for critical liquid-carrying flow rate does not fully consider the liquid droplets,liquid film flow velocity,and the dynamic changes of backflow fluid in gas core,as well as the complex wellbore configuration of shale gas horizontal well.In this context,based on the two-phase annular mist flow theory in wellbore,a critical liquid-carrying flow rate calculation model considering the liquid droplets,liquid film flow velocity,and the uneven thickness of liquid film in gas core for the entire section of shale gas horizontal well was established by using the liquid film model.The numerical solution of critical liquid-carrying flow rate was obtained by the Newton-Raphson Method,and the factors influencing the flow rate were analyzed.The results show that,(i)compared with the traditional calculation model,the new one yields the highest coincidence rate of prediction for wellbore liquid loading,with an accuracy up to 88.2%;(ii)the critical liquid-carrying flow rate increases and then decreases with the increase of wellbore inclination angle,reaching its maximum value at 36°;and(iii)the critical liquid-carrying flow rate increases with the increase of tubing inner diameter,decreases with the temperature increase,in-creases with the pressure increase,and decreases with the increase of liquid production.The established model provides guidance for predicting wellbore liquid loading in shale gas horizontal wells.
Shale gasHorizontal wellWellbore liquid loadingCritical liquid-carrying flow rateLiquid film model
万方数据
维普
