Effects of rock heterogeneity on hydraulic fracture propagation: A numerical study based on the combined finite-discrete element method

Wu，Mingyang1; Gao，Ke2; Song，Zhenlong2; Liu，Jianjun3

2021

55th U.S. Rock Mechanics / Geomechanics Symposium 2021

2

Material heterogeneity is commonplace in rock masses, and thus it is vital to investigate its influence on hydraulic fracture propagation in tight reservoir rocks. Here, based on the combined finite-discrete element method, two series of models with uniformly-distributed and Weibull-distributed elastic modulus of rock are assembled, respectively. The comparison with the theoretical solution demonstrates the reliability of the simulation models and simulation parameters in both the viscosity-dominated regime (VDR) and toughness-dominated regime (TDR). The effects of different Weibull distribution types on the variability of fracture length, final fracture morphology, fluid pressure at injection point, and maximum fracture aperture are evaluated. The results demonstrate that the distribution type of rock elastic modulus has a significant impact on the hydraulic fracture propagation in both the VDR and TDR. The “jump” phenomena have been observed in the TDR caused by high fracture toughness. The displacement of fracture location and asymmetrically dynamic propagation are affected by the distribution of rock elastic modulus. These results also indicate that the hydraulic fracture propagation in TDR is more susceptible to the distribution of rock elastic modulus than that in VDR. This research may shed light on the development of hydraulic fracturing technology in tight reservoir.

其他

英语

EI

20220311488446

Elastic moduli ; Fracture toughness ; Hydraulic fracturing ; Numerical methods ; Rock mechanics ; Weibull distribution

Soils and Soil Mechanics:483.1 ; Petroleum Deposits : Development Operations:512.1.2 ; Numerical Methods:921.6 ; Mathematical Statistics:922.2 ; Materials Science:951

2-s2.0-85122916706

Scopus

1.State Key Laboratory of Coal Mine Disaster Dynamics and Control,School of Resources and Safety Engineering,Chongqing University,Chongqing,400030,China
2.Department of Earth and Space Sciences,Southern University of Science and Technology,Shenzhen,518055,China
3.State Key Laboratory of Geomechanics and Geotechnical Engineering,Wuhan Institute of Rock and Soil Mechanics,Chinese Academy of Science,Wuhan,430071,China

Wu，Mingyang,Gao，Ke,Song，Zhenlong,et al. Effects of rock heterogeneity on hydraulic fracture propagation: A numerical study based on the combined finite-discrete element method[C],2021.