摘要
模拟预测压裂水平气井产量模型通常未考虑高速非达西流动的影响,特别是进行了多段压裂的水平气井的产能计算更未涉及。为此,将裂缝划分为若干单元,应用点源理论、气体不稳定渗流公式及势叠加原理,考虑N条裂缝同时产生相互干扰条件t时刻地层中任一点产生的总压降计算模型,以及高速非达西流动条件对压裂水平气井压后产能的影响,建立了更为完善的模拟预测压裂水平气井产能的新模型。实例模拟计算结果表明:压裂水平气井的产量随着生产时间的增加而逐渐降低且降低的幅度也不断减小;水平气井端部裂缝的产量最高,中部裂缝产量次之,中心裂缝产量最低;水平气井压后生产动态模拟预测新模型为优选高产水平气井横向裂缝数目和裂缝参数、确定合理生产压差提供了更准确的手段。
Generally, the simulation models of predicting the production of fractured horizontal gas wells never take into account the influence of the high speed non-Darcy flow, especially in the case of the production calculation of a multi stage fractured horizontal gas well. Thus, the fractures were first divided into different groups, then the point source theory, the unstable gas seepage formula and the potential superposition theory were adopted to establish the calculation model considering the total pressure drop of any point in the formation at the time t and under the mutual interferences simultaneously generated by the fractures with the number of N, and finally a better simulation model was built of predicting the production of a fractured horizontal gas well considering the impact of the high speed Darcy flow on a post-frac horizontal well. Case studies show that the production of a fractured horizontal well gradual- ly goes down over time, and downward margin decreases too; the fractures at the top of the horizontal well stand out for their high est gas output, followed by those in the middle and the lowest by those in the center; this new simulation model is a more accurate tool to determine an optimized number of horizontal fractures and more suitable fracture parameters for a more reasonable drawdown pressure.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2013年第1期61-64,共4页
Natural Gas Industry
关键词
水平井
气井
多段压裂
高速非达西流动
不稳定渗流
生产模拟
数学模型
horizontal well, gas well, multi-stage fracturing, high speed non-Darcy flow, unstable seepage, production simulation,mathematical model
