Study on multiple-fracture extension within a stage in horizontal well of tight reservoir
YANG Zhaozhong1，YI Liangping1，LI Xiaogang1，LIU Changyin2
(1. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation，Southwest Petroleum University，Chengdu，Sichuan 610500，China；2. Petroleum Exploration and Production Research Institute，SINOPEC，Beijing 100083，China)
In order to study the mechanism of multiple-fracture unevenly growth in multi-cluster fracturing，we simultaneously consider the stress interference among fractures and dynamic flow distribution among clusters to establisha set of control equations for multiple-fracture propagationwithin a stage，and the equations are solved by Picard iteration method. In the model the multiple-fracturepropagationvelocity is determined by the energy release rate. The stress interference and fracture width are calculated by displacement discontinuity method，and dynamic flow distribution among clusters are calculated according toKirchhoff¢s second law.Based on the established model，an example of X201 well in Xinjiang is analyzed. The results show that when the cluster spacing is 20m，interior clusters are severely restricted. Under the condition of four clusters fracturing，only increasing the internal clusters spacing has little influence on promoting multiple-fracture even propagation. Adjusting perforation friction can promote internal two clusters effective extension. Simultaneously adjusting the clusters spacing and perforation friction is more likely than only adjusting one to promote multiple-fracture uniform propagation.
杨兆中1，易良平1，李小刚1，刘长印2. 致密储层水平井段内多簇压裂多裂缝扩展研究[J]. 岩石力学与工程学报, 2018, 37(S2): 3870-3878.
YANG Zhaozhong1，YI Liangping1，LI Xiaogang1，LIU Changyin2. Study on multiple-fracture extension within a stage in horizontal well of tight reservoir. , 2018, 37(S2): 3870-3878.
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2018, Vol. 37 
