引用本文: 张磊, 吴克柳. 基于双循环的气井产量劈分方法及应用[J]. 工程科学学报.
A production splitting method for gas wells based on double cycles and its application[J]. Chinese Journal of Engineering.
 Citation: A production splitting method for gas wells based on double cycles and its application[J]. Chinese Journal of Engineering.

A production splitting method for gas wells based on double cycles and its application

• 摘要: 产量劈分系数的求解关键参数为泄气半径，但泄气半径通常未知，结合产能方程和物质平衡方程，建立了闭环的产量劈分系数计算模型，提出了双循环计算法，内循环求解泄气半径，外循环求解产量劈分系数，内循环和外循环均存在唯一解，循环规则包括正向递归和反向递归，内循环与外循环的循环规则始终相反，通过设定循环步长和误差上限，建立了双循环的计算流程，外循环包含内循环，内循环收敛时外循环才能进行，外循环决定了内循环能否收敛。产量劈分系数在不同产层、不同阶段、不同时间表现出不同的变化规律，数值模拟验证表明，双循环计算法的机理正确且精度很高。产气剖面对比显示，双循环计算法在现场应用中亦具有可靠的精度。双循环计算法属于三元方程组的求解方法，实现了产量劈分系数、泄气半径和平均地层压力的同时计算。

Abstract: The key parameter to calculate the production splitting coefficient is the gas drainage radius, which is usually unknown. Combining the productivity equation and material balance equation, a closed loop calculation model of production splitting coefficient is established, and the calculation method for internal and external double circles is proposed, where the internal and external circles are used to solve the gas drainage radius and the production splitting coefficient, respectively. Both the internal and external circles have unique solutions. The circle rules include forward recursion and reverse recursion, and the internal and external circles have the opposite circle rules. By setting the step size of cycle and the upper limit of error, the calculation process of double cycles is established. The external cycle includes the internal cycle, and it can only be realized when the internal cycle converges, moreover, it determines whether the internal cycle can converge. The production splitting coefficient shows different variation laws in different production layers at different producing stages and times. The numerical simulation results show that the mechanism of the double circles is correct and highly accurate. The gas production profiles show that the internal and external double circle also has a good accuracy in field application. The double cycle is a method of solving ternary equation group, which can calculate the production splitting coefficient, gas drainage radius and average formation pressure at the same time.

/

• 分享
• 用微信扫码二维码

分享至好友和朋友圈