页岩气藏水平井分段多簇压裂复杂裂缝产量模拟

现有页岩储层压裂水平井产能预测模型均采用与实际不符的平面裂缝假设，压后产能预测不准确。针对页岩储层压裂裂缝非对称非平面的实际复杂形态，基于流体扩散理论和压降叠加原理，建立了气藏渗流和裂缝渗流模型，采用空间离散建立了产量计算模型，通过数值分析方法求解，对页岩气藏水平井分段多簇压裂复杂裂缝产量进行了模拟。结果表明：真实非平面复杂裂缝产量远高于理想平面裂缝产量；天然裂缝对非平面裂缝形态和产量具有重要影响；三簇同时延伸形成的裂缝，中间缝产量比外侧缝产量低，产量差距在生产初期较大，随着时间增加，差距减小。外侧裂缝对导流能力比中间缝敏感；随着裂缝导流能力的增加，产量增加，但并非线性关系，增加的幅度逐渐减小。

Production simulation of staged multi-cluster fractured horizontal#br#wells with complex hydraulic fracture in shale gas reservoirs

The existing productivity prediction models of fractured horizontal well for shale gas reservoir are based on the assumption of planar hydraulic fracture.However,the actual geometry of hydraulic fracture in shale reservoirs is complex.So the productivity prediction is not accurate.In view of the actual asymmetric non-planar complex fracture geometry in shale gas reservoir,a gas reservoir seepage model and a hydraulic fracture seepage model are established.A new productivity model is set up with the semi-analytical method.By numerical analysis way,we calculated the production of staged multi-cluster fractured horizontal well with complex hydraulic fracture.The results of production simulation indicate that the gas production from real non-planar fracture is much greater than the gas production from ideal planar fracture.Natural fractures have an enormous impact on the non-planar fracture geometry and well productivity.After three fractures extend at the same time,the production of middle one is smaller than the production of lateral ones,and production gap is larger at the beginning of production.With the increase of time,the production gap becomes smaller.The lateral fractures are more sensitive to fracture conductivity than the middle one.With the increase of fracture conductivity,the production of non-planar fractures increases.But it is not a linear relationship,the increasing amplitude decreases.