A hydraulic fracture height mathematical model considering the influence of plastic region at fracture tip

• 作者: CHEN Mian FU Xiaofei LI Yuwei LONG Min TANG Jizhou
• 来源期刊: 石油勘探与开发:英文版
• 学科: 工学
• 关键词: hydraulic FRACTURING FRACTURE HEIGHT plastic region at FRACTURE TIP FRACTURE TOUGHNESS multi-layered formation with high IN-SITU stresses
• 年，卷（期）: 2020,（1）
• 页码范围: 184-195
• 页数: 12页
• 分类号: TE357.1

摘要

To predict fracture height in hydraulic fracturing, we developed and solved a hydraulic fracture height mathematical model aiming at high stress and multi-layered complex formations based on studying the effect of plastic region generated by stress concentration at fracture tip on the growth of fracture height. Moreover, we compared the results from this model with results from two other fracture height prediction models(MFEH, Frac Pro) to verify the accuracy of the model. Sensitivity analysis by case computation of the model shows that the hydraulic fracture growth in ladder pattern, and the larger the fracture height, the more obvious the ladder growth pattern is. Fracture height growth is mainly influenced by the in-situ stresses. Fracture toughness of rock can prohibit the growth of fracture height to some extent. Moreover, the increase of fracturing fluid density can facilitate the propagation of the lower fracture tip.