Abstract:

For low production and low efficiency wells, interval production is usually used to tap potential. However, most practices are based on qualitative and benefit factors to determine interval production parameters, which are lack of scientific accuracy. In order to optimize and study the interval production parameters more precisely and quantitatively, combining the theoretical basis of material balance, inflow and outflow dynamics and other parameters such as well deviation and reservoir physical properties are taken into account, the mathematical model of fluid level coupling in the switch well for interval oil production is established. The coupling model calculation results are innovatively matched with the measured dynamic level recovery curve to obtain the reservoir physical parameters. On the basis of the above, the dynamic liquid level during shut in and pumping is divided into equal parts by enumeration method, the reasonable working parameters are determined by optimizing and evaluating the wellhead production, pump efficiency and formation inflow. The field application verification shows that: fitting the numerical iteration results of the coupled mathematical model with the measured liquid level recovery curve, it can more scientifically determine the interval production parameters. At the same time, it also ensures that the oil wells are in an efficient and coordinated supply and discharge relationship.

Key words: coupled mathematical models, pump efficiency, interval production, working system, dynamic liquid level recovery curve