The Experts below are selected from a list of 327 Experts worldwide ranked by ideXlab platform

Dongxiao Zhang - One of the best experts on this subject based on the ideXlab platform.

  • coupled fluid flow and Geomechanics for triple porosity dual permeability modeling of coalbed methane recovery
    International Journal of Rock Mechanics and Mining Sciences, 2010
    Co-Authors: Zhijie Wei, Dongxiao Zhang
    Abstract:

    Abstract A coupled fluid-flow and Geomechanics model for simulating coalbed methane (CBM) recovery is presented. In the model, the fluid-flow process is simulated with a triple-porosity/dual-permeability model, and the coupling effects of effective stress and micro-pore swelling/shrinkage are modeled with the coupled fluid-flow and geomechanical deformation approach. The mathematical model is implemented with a finite volume method. First, a case without considering coupling between fluid-flow and Geomechanics is simulated and compared with an existing simulator. The effects of coupled fluid-flow and Geomechanics are then studied in detail with two illustrative examples. The first one is designed for testing the effective stress effect without micro-pore swelling/shrinkage effect, and the other for testing the coupling effects of the effective stress and micro-pore swelling/shrinkage on the methane production. The numerical results indicate that both the effective stress and the micro-pore shrinkage make a significant contribution to fluid-flow in CBM reservoir and to methane production. The methane production sensitivity to Young’s modulus and Langmuir sorption strain are investigated as well. Finally, we make a dynamic analysis of the coupling effects of fluid-flow process and Geomechanics.

  • COUPLED FLUID FLOW AND Geomechanics IN COALBED METHANE RECOVERY STUDY
    Modern Physics Letters B, 2010
    Co-Authors: Zhijie Wei, Dongxiao Zhang
    Abstract:

    In this paper, we present a coupled fluid flow and Geomechanics model for simulating coalbed methane recovery. In the model, the fluid flow process is simulated with a triple porosity/dual permeability representation, and the coupling effects of effective stress and matrix swelling/shrinkage approach are simulated with a coupled fluid flow, Geomechanics and gas adsorption/desorption model. The mathematical model is implemented with a fully implicit finite volume method and simulation is conducted to evaluate the effect of coupled fluid flow, Geomechanics, and gas adsorption/desorption.

  • Coupled fluid-flow and Geomechanics for triple-porosity/dual-permeability modeling of coalbed methane recovery
    International Journal of Rock Mechanics and Mining Sciences, 2010
    Co-Authors: Zhijie Wei, Dongxiao Zhang
    Abstract:

    Abstract A coupled fluid-flow and Geomechanics model for simulating coalbed methane (CBM) recovery is presented. In the model, the fluid-flow process is simulated with a triple-porosity/dual-permeability model, and the coupling effects of effective stress and micro-pore swelling/shrinkage are modeled with the coupled fluid-flow and geomechanical deformation approach. The mathematical model is implemented with a finite volume method. First, a case without considering coupling between fluid-flow and Geomechanics is simulated and compared with an existing simulator. The effects of coupled fluid-flow and Geomechanics are then studied in detail with two illustrative examples. The first one is designed for testing the effective stress effect without micro-pore swelling/shrinkage effect, and the other for testing the coupling effects of the effective stress and micro-pore swelling/shrinkage on the methane production. The numerical results indicate that both the effective stress and the micro-pore shrinkage make a significant contribution to fluid-flow in CBM reservoir and to methane production. The methane production sensitivity to Young’s modulus and Langmuir sorption strain are investigated as well. Finally, we make a dynamic analysis of the coupling effects of fluid-flow process and Geomechanics.

Kamy Sepehrnoori - One of the best experts on this subject based on the ideXlab platform.

  • Simulation of gas desorption and Geomechanics effects for unconventional gas reservoirs
    Fuel, 2014
    Co-Authors: Kamy Sepehrnoori
    Abstract:

    Abstract Hydraulic fracturing of horizontal wells is crucial for economic production of shale gas. Impacts of gas desorption and Geomechanics in hydraulic fractures on ultimate gas recovery are not clearly understood and systematically investigated. In this paper, we perform history matching with two field gas production data from Barnett Shale and Marcellus Shale, and first analyze the positive contribution of gas desorption and the negative effect of Geomechanics on gas production, respectively, and then compare these two effects on gas production with the purpose of identifying which effect is dominant in the whole process of gas production. Furthermore, we numerically study the effect of gas desorption on gas recovery with available laboratory data of Langmuir isotherm from five different shale formations including Barnett Shale, New Albany Shale, Eagleford Shale, Marcellus Shale, and Haynesville Shale. Also, we use the method of Design of Experiment to perform sensitivity studies with six uncertain parameters such as reservoir permeability, bottom hole pressure, fracture conductivity, initial reservoir pressure, porosity, and fracture spacing to screen insignificant parameters and obtain critical parameters that control this process. This paper enables operators to develop an early better understanding of the effects of gas desorption and Geomechanics on shale gas well performance, and provides insights into history matching and optimization of hydraulic fracturing treatment design for shale gas production.

George J Moridis - One of the best experts on this subject based on the ideXlab platform.

  • Development of the T+M coupled flow-geomechanical simulator to describe fracture propagation and coupled flow-thermal-geomechanical processes in tight/shale gas systems
    Computers and Geosciences, 2013
    Co-Authors: Jihoon Kim, George J Moridis
    Abstract:

    We developed a hydraulic fracturing simulator by coupling a flow simulator to a Geomechanics code, namely T+M simulator. Modeling of the vertical fracture development involves continuous updating of the boundary conditions and of the data connectivity, based on the finite element method for Geomechanics. The T+M simulator can model the initial fracture development during the hydraulic fracturing operations, after which the domain description changes from single continuum to double or multiple continua in order to rigorously model both flow and Geomechanics for fracture-rock matrix systems. The T+H simulator provides two-way coupling between fluid-heat flow and Geomechanics, accounting for thermo-poro-mechanics, treats nonlinear permeability and geomechanical moduli explicitly, and dynamically tracks changes in the fracture(s) and in the pore volume. We also fully account for leak-off in all directions during hydraulic fracturing.We first test the T+M simulator, matching numerical solutions with the analytical solutions for poromechanical effects, static fractures, and fracture propagations. Then, from numerical simulation of various cases of the planar fracture propagation, shear failure can limit the vertical fracture propagation of tensile failure, because of leak-off into the reservoirs. Slow injection causes more leak-off, compared with fast injection, when the same amount of fluid is injected. Changes in initial total stress and contributions of shear effective stress to tensile failure can also affect formation of the fractured areas, and the geomechanical responses are still well-posed. © 2013 .

Hanyi Wang - One of the best experts on this subject based on the ideXlab platform.

Jonny Rutqvist - One of the best experts on this subject based on the ideXlab platform.

  • Extension of TOUGH-FLAC to the finite strain framework
    Computers & Geosciences, 2017
    Co-Authors: Laura Blanco-martín, Jonny Rutqvist, Jt Birkholzer
    Abstract:

    Abstract The TOUGH-FLAC simulator for coupled thermal-hydraulic-mechanical processes modeling has been extended to the finite strain framework. In the approach selected, this extension has required modifications to the flow simulator (TOUGH2) and to the coupling scheme between the Geomechanics and the flow sub-problems. In TOUGH2, the mass and energy balance equations have been extended to account for volume changes. Additionally, as large deformations are computed by FLAC3D, the geometry is updated in the flow sub-problem. The Voronoi partition needed in TOUGH2 is computed using an external open source library (Voro++) that uses the centroids of the deformed Geomechanics mesh as generators of the Voronoi diagram. TOUGH-FLAC in infinitesimal and finite strain frameworks is verified against analytical solutions and other approaches to couple flow and Geomechanics. Within the finite strain framework, TOUGH-FLAC is also successfully applied to a large-scale case. The extension of TOUGH-FLAC to the finite strain framework has little impact to the user as only one additional executable is needed (for Voro++), and the input files and the workflow of a simulation are the same as in standard TOUGH-FLAC. With this new provision for finite strains, TOUGH-FLAC can be used in the analysis of a wider range of engineering problems, and the areas of application of this simulator are therefore broadened.

  • An overview of TOUGH-based Geomechanics models
    Computers & Geosciences, 2017
    Co-Authors: Jonny Rutqvist
    Abstract:

    After the initial development of the first TOUGH-based Geomechanics model 15 years ago based on linking TOUGH2 multiphase flow simulator to the FLAC3D Geomechanics simulator, at least 15 additional TOUGH-based Geomechanics models have appeared in the literature. This development has been fueled by a growing demand and interest for modeling coupled multiphase flow and geomechanical processes related to a number of geoengineering applications, such as in geologic CO2 sequestration, enhanced geothermal systems, unconventional hydrocarbon production, and most recently, related to reservoir stimulation and injection-induced seismicity. This paper provides a brief overview of these TOUGH-based Geomechanics models, focusing on some of the most frequently applied to a diverse set of problems associated with Geomechanics and its couplings to hydraulic, thermal and chemical processes. A brief overview of over 15 TOUGH-based Geomechanics models.More detailed description of the most applied, including TOUGH-FLAC.Recent model developments related to hydraulic fracturing.