Development of the T+M coupled flow–geomechanical simulator to describe fracture propagation and coupled flow–thermal–geomechanical processes in tight/shale gas systems

Kim, Jihoon; Moridis, George J.

doi:10.1016/j.cageo.2013.04.023

Cited by 63 publications

(42 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For time discretization, we use the backward Euler method, which is typically used in reservoir simulation. We use TOUGH+RealGasH2O as a fluid and heat flow simulator and ROCMECH for a geomechanics simulator, namely T+M, developed in the Lawrence Berkeley National Laboratory (Kim and Moridis, 2013), using a sequential implicit method, called the fixed-stress sequential method.…”

Section: Numerical Implementationmentioning

confidence: 99%

“…The porosity correction term,  , is calculated from geomechanics, which corrects the porosity estimated from the pore compressibility. The fixed-stress sequential method solves two-way coupling between flow and geomechanics, so it captures the Mandel-Cryer effects, solving Mandel's problem correctly, which cannot be simulated by the uncoupled simulation (Kim and Moridis, 2013). When implementing the Mohr-Coulomb model, we reference the algorithms proposed by Wang et al (2004).…”

Section: Numerical Implementationmentioning

confidence: 99%

See 1 more Smart Citation

Investigation of possible wellbore cement failures during hydraulic fracturing operations

Kim

Moridis

Martínez

2016

Journal of Petroleum Science and Engineering

Self Cite

View full text Add to dashboard Cite

We model and assess the possibility of shear failure, using the Mohr-Coulomb model -along the vertical well by employing a rigorous coupled flow-geomechanic analysis. To this end, we vary the values of cohesion between the well casing and the surrounding cement to representing different quality levels of the cementing operation (low cohesion corresponds to low-quality cement and/or incomplete cementing). The simulation results show that there is very little fracturing when the cement is of high quality.. Conversely, incomplete cementing and/or weak cement can causes significant shear failure and the evolution of long fractures/cracks along the vertical well. Specifically, low cohesion between the well and cemented areas can cause significant shear failure along the well, but the same cohesion as the cemented zone does not cause shear failure. When the hydraulic fracturing pressure is high, low cohesion of the cement can causes fast propagation of shear failure and of the resulting fracture/crack, but a highquality cement with no weak zones exhibits limited shear failure that is concentrated near the bottom of the vertical part of the well. Thus, high-quality cement and complete cementing along the vertical well appears to be the strongest protection against shear failure of the wellbore cement and, consequently, against contamination hazards to drinking water aquifers during hydraulic fracturing operations.

show abstract

Section: Numerical Implementationmentioning

confidence: 99%

Section: Numerical Implementationmentioning

confidence: 99%

Investigation of possible wellbore cement failures during hydraulic fracturing operations

Kim

Moridis

Martínez

2016

Journal of Petroleum Science and Engineering

Self Cite

View full text Add to dashboard Cite

show abstract

“…We use TOUGH+RealGasH2O as a fluid and heat flow simulator and ROCMECH for a geomechanics simulator, namely T+M, recently developed in the Lawrence Berkeley National Laboratory (Kim and Moridis, 2013).…”

Section: Numerical Implementationmentioning

confidence: 99%

Section: Numerical Implementationmentioning

confidence: 99%

Gas Flow Tightly Coupled to Elastoplastic Geomechanics for Tight and Shale Gas Reservoirs: Material Failure and Enhanced Permeability

Kim

Moridis

2012

All Days

Self Cite

View full text Add to dashboard Cite

We investigate coupled flow and geomechanics in gas production from extremely low permeability reservoirs such as tight and shale gas reservoirs, using dynamic porosity and permeability during numerical simulation. In particular, we take the intrinsic permeability as a step function of the status of material failure, and the permeability is updated every time step. We consider gas reservoirs with the vertical and horizontal primary fractures, employing the single and dynamic double porosity (dual continuum) models. We modify the multiple porosity constitutive relations for modeling the double porous continua for flow and geomechanics. The numerical results indicate that production of gas causes redistribution of the effective stress fields, increasing the effective shear stress and resulting in plasticity. Shear failure occurs not only near the fracture tips but also away from the primary fractures, which indicates generation of secondary fractures. These secondary fractures increase the permeability significantly, and change the flow pattern, which in turn causes a change in distribution of geomechanical variables. From various numerical tests, we find that shear failure is enhanced by a large pressure drop at the production well, high Biot's coefficient, low frictional and dilation angles. Smaller spacing between the horizontal wells also contributes to faster secondary fracturing. When the dynamic double porosity model is used, we observe a faster evolution of the enhanced permeability areas than that obtained from the single porosity model, mainly due to a higher permeability of the fractures in the double porosity model. These complicated physics for stress sensitive reservoirs cannot properly be captured by the uncoupled or flow-only simulation, and thus tightly coupled flow and geomechanical models are highly recommended to accurately describe the reservoir behavior during gas production in tight and shale gas reservoirs and to smartly design production scenarios. IntroductionUnconventional natural gas such as tight and shale gas has become an increasingly important source of natural gas in the United States over the past decade and the estimates of the natural gas resource potential for shale gas range from 14.16×10

show abstract

“…This approach makes it easy to understand reservoir variations, and is useful for industry application. On the other hand, the researchers focus on conductivity of fractures with numerical simulations using the finite volume method (FVM), finite element method (FEM) and Newton method (NM), which uses the linear part of Taylor's formula to solve nonlinear problems [13,14]. Ren et al proposed an extended finite element method-embedded discrete fracture model (XFEM-EDFM) and a proppant model to analyze the influence of stress-dependent fracture permeability on cumulative production [15].…”

Section: Introductionmentioning

confidence: 99%

Analytical modeling of coupled flow and geomechanics for vertical fractured well in tight gas reservoirs

et al. 2017

View full text Add to dashboard Cite

Abstract:The mathematical model of coupled flow and geomechanics for a vertical fractured well in tight gas reservoirs was established. The analytical modeling of unidirectional flow and radial flow was achieved by Laplace transforms and integral transforms. The results show that uncoupled flow would lead to an overestimate in performance of a vertical fractured well, especially in the later stage. The production rate decreases with elastic modulus because porosity and permeability decrease accordingly. Drawdown pressure should be optimized to lower the impact of coupled flow and geomechanics as a result of permeability decreasing. Production rate increases with fracture half-length significantly in the initial stage and becomes stable gradually. This study could provide a theoretical basis for effective development of tight gas reservoirs.

show abstract

Development of the T+M coupled flow–geomechanical simulator to describe fracture propagation and coupled flow–thermal–geomechanical processes in tight/shale gas systems

Cited by 63 publications

References 38 publications

Investigation of possible wellbore cement failures during hydraulic fracturing operations

Investigation of possible wellbore cement failures during hydraulic fracturing operations

Gas Flow Tightly Coupled to Elastoplastic Geomechanics for Tight and Shale Gas Reservoirs: Material Failure and Enhanced Permeability

Analytical modeling of coupled flow and geomechanics for vertical fractured well in tight gas reservoirs

Contact Info

Product

Resources

About