Shale gas reservoir is usually developed by multi-fractured horizontal well, and stimulated reservoir volume dominates the gas rate as the main factor. For the heterogeneity of formation, both size and distribution of each fracturing area are not uniform. To investigate effect of heterogeneous fracturing on rate decline of multiple fractured horizontal well in shale gas reservoir, by introducing the parameters of different stimulated area's size and location in equations, a mathematical model based on horizontal well lfow equations is established. Analytical solution and rate decline curve for model are presented then. The lfow regimes are divided in gas rate dechlin curve, and curves characters of different un-uniform fracturing types are analyzed. The result shows that heterogeneity of fracturing affects production rate and linear lfow stage. With more heterogenous of fracturing, the gas rate becomes fewer and duration of linear lfow period is longer. Example analysis shows that the model can be used for production prediction of multiple fractured horizontal wells. This approach provides a theoretical basis on production lfow decline prediction.%页岩气藏普遍采用水平井体积压裂方式开发，压裂体积是影响气井产气特征的重要因素。在实际开发中，由于储层非均质性等影响，各压裂段压裂体积各不相同。为研究压裂体非均匀展布对产能递减规律的影响，根据页岩气渗流特征，在水平井渗流模型的基础上，引入压裂体大小及分布等表征参数，建立了页岩气藏非均匀压裂水平井渗流模型，并绘制了产能递减曲线。同时根据典型产量递减曲线划分了流动阶段，分析评价了不同压裂体展布类型下产量递减曲线特征。研究表明压裂体的展布特征主要影响产气量及线性流阶段曲线特征；非均匀压裂造成水平井产气量较少、早期线性流持续时间较长。结合压裂数据，提出了气井产量预测方法并进行了实例计算。
展开▼
