دورية أكاديمية

Numerical simulation of hydraulic fracturing based on two-dimensional surface fracture morphology reconstruction and combined finite-discrete element method.

التفاصيل البيبلوغرافية
العنوان: Numerical simulation of hydraulic fracturing based on two-dimensional surface fracture morphology reconstruction and combined finite-discrete element method.
المؤلفون: Wu, M.Y., Zhang, D.M., Wang, W.S., Li, M.H., Liu, S.M., Lu, J., Gao, H.
المصدر: Journal of Natural Gas Science & Engineering; Oct2020, Vol. 82, pN.PAG-N.PAG, 1p
مصطلحات موضوعية: HYDRAULIC fracturing, SURFACE morphology, GEOLOGICAL modeling, FLUID pressure, COMPUTER simulation, SHALE gas, ELASTIC modulus
مستخلص: Hydraulic fracturing is an important technology widely applied in engineering practice for the exploitation of unconventional oil and gas resources. Further research on its mechanism has the potential to advance the development of unconventional reservoir exploitation. In this study, previously acquired experimental data, including surface fracture image and fluid pressure curve, were used for modelling and comparison. Employing digital core reconstruction and the combined finite-discrete element method, A process of modelling crack geological model was proposed based on the rock surface sketch after fracturing. Two-dimensional models were established according to the surface fracture morphology of specimens. The feasibility of these numerical models was simultaneously verified by fluid pressure curves and the surface fracture morphology obtained in physical experiments. The evolution of fracture morphology during hydraulic fracturing was analysed. Simulation results indicate that: (1) the simulation method of this study is more suitable for simulation of coal hydraulic fracturing than for shale hydraulic fracturing; (2) the rapid rise of fluid pressure might be accompanied with the initiation and development of micro-fractures, leading to the occurrence of larger fractures; (3) the hydraulic fracturing process on the experimental scale could induce significantly larger maximum total area and wider fractures in coal specimens than in shale specimens. This indicates that coal hydraulic fracturing forms more complex fractures than in shale; (4) when the rock elastic modulus increases, the maximum fracture width and fracture total area decreases, and fracture length is extended. (5) The initiation and propagation pressures are positively related to the elastic modulus in the fluid pressure evolution. The crack geological model proposed in this study provides direct guidance for crack reconstruction in simulations. Moreover, the research results may provide a guidance for studies on the evolution of hydraulic fracture under the influence of rock heterogeneity. • A process of modelling crack geological model was proposed based on rock surface sketch after fracturing. • The hydraulic fracturing process in experiment and numerical simulation was compared. • Characteristics of hydraulic fracture morphology evolution were revealed at the experimental scale. • Coal hydraulic fracturing forms more complex fractures than in shale. [ABSTRACT FROM AUTHOR]
Copyright of Journal of Natural Gas Science & Engineering is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
قاعدة البيانات: Supplemental Index
الوصف
تدمد:18755100
DOI:10.1016/j.jngse.2020.103479