... Flaherty, Joseph E., Paslow, Pamela J., Shephard, Mark S., and Vasilakis, John D., Adaptive .... more ... Flaherty, Joseph E., Paslow, Pamela J., Shephard, Mark S., and Vasilakis, John D., Adaptive ... Annual ACM-SIAM Symposium on Discrete Algorithms (1998) DeSanto, John A., Mathematical ... for High-Performance Scientific Applications Andrew Cleary, Scott Kohn, Steven G. Smith ...
International Petroleum Technology Conference, 2005
Fractured and fracture-enhanced reservoirs are becoming increasingly important as the world's... more Fractured and fracture-enhanced reservoirs are becoming increasingly important as the world's remaining hydrocarbon assets are developed. New modeling and simulation techniques must be developed to guide business decisions, improve economic forecasts, and maximize productivity. To address this need, a fractured reservoir modeling and simulation workflow was developed to integrate evolving technology for fracture characterization, geologic modeling, and flow simulation. The workflow is based on: common-scale geologic and simulation models;fine-scale element models to compute effective matrix permeability;analysis of fracture data from core, image logs, and outcrop; andintegration of field performance, structure, stratigraphy, and lithology. Directional equivalent fracture permeability, porosity, and matrix block dimensions are estimated using discrete fracture network (DFN) and 3D geologic models, while effective matrix permeability is derived using proprietary technology (patent...
We develop an ELLAM-MFEM approximation to the strongly coupled systems of time-dependent nonlinea... more We develop an ELLAM-MFEM approximation to the strongly coupled systems of time-dependent nonlinear partial differential equations (PDEs) and constraining equations, which describe fully miscible, highly compressible, multicomponent flows through heterogeneous and compressible porous media with singular sources and sinks. An Eulerian–Lagrangian localized adjoint method (ELLAM) is presented to solve the transport equations for concentrations. A mixed finite element method (MFEM) is used to solve the pressure PDE for the pressure and Darcy velocity simultaneously, which generates accurate fluid velocities and minimizes the numerical difficulties occurring in standard methods caused by differentiation of the pressure and then multiplication by rough coefficients. The ELLAM-MFEM solution technique symmetrizes and stabilizes the governing transport PDEs and greatly reduces nonphysical oscillation and/or excessive numerical dispersion present in many large-scale simulators. Computational experiments show that the ELLAM-MFEM solution technique can generate stable and physically reasonable numerical simulations even if coarse spatial grids and very large time steps are used.
Numerical simulation of uid ow in a hydrocarbon reservoir has to account for the presence of well... more Numerical simulation of uid ow in a hydrocarbon reservoir has to account for the presence of wells. The pressure of a grid cell containing a well is diierent from the average pressure in that cell and diierent from the bottomhole pressure for the well (Peaceman, 17]). This paper presents a study of grid pressures obtained from the simulation of single phase ow through an isotropic porous medium using diierent numerical methods. Well equations are proposed for Darcy ow with Galerkin nite elements and mixed nite elements. Furthermore, high velocity (non-Darcy) ow well equations are developed for cell-centered nite diierence, Galerkin nite element and mixed nite element techniques.
... Flaherty, Joseph E., Paslow, Pamela J., Shephard, Mark S., and Vasilakis, John D., Adaptive .... more ... Flaherty, Joseph E., Paslow, Pamela J., Shephard, Mark S., and Vasilakis, John D., Adaptive ... Annual ACM-SIAM Symposium on Discrete Algorithms (1998) DeSanto, John A., Mathematical ... for High-Performance Scientific Applications Andrew Cleary, Scott Kohn, Steven G. Smith ...
ABSTRACT We present an ELLAM-MFEM simulator for accurate, efficient, and robust simulations to hi... more ABSTRACT We present an ELLAM-MFEM simulator for accurate, efficient, and robust simulations to highly compressible flows in porous media with multiple wells. An Eulerian-Lagrangian localized adjoint method (ELLAM) is used to solve the advection-diffusion transport partial differential equation for concentration, while a mixed finite element method (MFEM) is used to solve the pressure equation for the pressure and mass flow rate. The ELLAM-MFEM simulator symmetrizes the transport equation, and eliminates nonphysical oscillation and/or excessive numerical dispersion in many large-scale simulators in industrial applications. Computational experiments show that the ELLAM-MFEM simulator can accurately simulate incompressible and compressible flows in porous media with multiple and different types of wells, large mobility ratios, discontinuous permeabilities and porosities, and anisotropic dispersion in tensor form, even if very large time steps and spatial grids are used.
An accurate and efficient simulator is developed for compressible flow porous media with wells. A... more An accurate and efficient simulator is developed for compressible flow porous media with wells. An Eulerian-Lagrangian localized adjoint method (ELLAM) is used to solve the transport partial differential equation for concentration, while a mixed finite element method (MFEM) is used to solve the pressure equation for the pressure and mass flow rate. The ELLAM-MFEM simulator symmetrizes the transport equation, eliminates nonphysical oscillation and/or excessive numerical dispersion in many large-scale simulators in industrial applications, and conserves mass. It minimizes the numerical difficulties occurring in standard methods caused by differentiation of the pressure and then multiplication by rough coefficients. Computational experiments show that the ELLAM-MFEM simulator can accurately simulate incompressible and compressible flows in porous media with wells, large mobility ratios, discontinuous permeabilities and porosities, and anisotropic dispersion in tensor form, even if very large time steps and spatial grids are used.
Model-Based Uncertainty Analysis (MBUA) is a method to evaluate reservoir performance uncertainty... more Model-Based Uncertainty Analysis (MBUA) is a method to evaluate reservoir performance uncertainty using multiple 3D models. Experimental Design techniques are used to determine what 3D models are built (unique geologic models which are then simulated) based on the number of identified uncertain factors. This method captures main effects and factor interactions and results in a multivariable response surface for each desired outcome (e.g. expected ultimate recovery, original hydrocarbon in place) which can be used for Monte Carlo simulations. The entire MBUA process results in tornado plots, exceedence curves, and a method to build representative models. A key strength of the MBUA process is the ability to capture dynamic responses such as water rate, production at early times, and plateau length. These responses provide project teams a greater understanding of how their subsurface uncertainties impact field performance and can help guide additional technical work, development planning decisions and representative model building. We have applied either a full or partial MBUA process to several fields for the purposes of identifying key technical uncertainties and improving the development plan across likely outcomes. Once an initial base case model has been built, subsequent models (totaling 16-54 models) can be rapidly built and simulated using normal geologic and flow simulation model workflows. While the analysis is quick, all model results are required to complete the analysis, thus simulation time is the biggest bottleneck in the process. Production data have been incorporated through either history-matching the initial base case or examining Monte Carlo simulation results for potential trends. The uncertainty analysis provides a streamlined process to examine potential uncertainty factors and allows a project to make informed decisions regarding future technical work or potential mitigation plans. A process overview will be presented along with sample results and lessons from completing the full MBUA.
Model-Based Uncertainty Analysis (MBUA) is a method to evaluate reservoir performance uncertainty... more Model-Based Uncertainty Analysis (MBUA) is a method to evaluate reservoir performance uncertainty using multiple 3D models. Experimental Design techniques are used to determine what 3D models are built (unique geologic models which are then simulated) based on the number of identified uncertain factors. This method captures main effects and factor interactions and results in a multivariable response surface for each desired outcome (e.g. expected ultimate recovery, original hydrocarbon in place) which can be used for Monte Carlo simulations. The entire MBUA process results in tornado plots, exceedence curves, and a method to build representative models. A key strength of the MBUA process is the ability to capture dynamic responses such as water rate, production at early times, and plateau length. These responses provide project teams a greater understanding of how their subsurface uncertainties impact field performance and can help guide additional technical work, development planni...
This paper describes the coupling of a pipeline network model to a reservoir simulator and its ap... more This paper describes the coupling of a pipeline network model to a reservoir simulator and its application to optimize the production strategy of two Mobil field developments. Mobil`s PEGASUS simulator is an integrated, all-purpose reservoir simulator that handles black-oil, compositional, faulted, and naturally fractured reservoirs. The authors have extended the simulator to allow simultaneous modeling of multiple reservoirs coupled with
... Flaherty, Joseph E., Paslow, Pamela J., Shephard, Mark S., and Vasilakis, John D., Adaptive .... more ... Flaherty, Joseph E., Paslow, Pamela J., Shephard, Mark S., and Vasilakis, John D., Adaptive ... Annual ACM-SIAM Symposium on Discrete Algorithms (1998) DeSanto, John A., Mathematical ... for High-Performance Scientific Applications Andrew Cleary, Scott Kohn, Steven G. Smith ...
International Petroleum Technology Conference, 2005
Fractured and fracture-enhanced reservoirs are becoming increasingly important as the world's... more Fractured and fracture-enhanced reservoirs are becoming increasingly important as the world's remaining hydrocarbon assets are developed. New modeling and simulation techniques must be developed to guide business decisions, improve economic forecasts, and maximize productivity. To address this need, a fractured reservoir modeling and simulation workflow was developed to integrate evolving technology for fracture characterization, geologic modeling, and flow simulation. The workflow is based on: common-scale geologic and simulation models;fine-scale element models to compute effective matrix permeability;analysis of fracture data from core, image logs, and outcrop; andintegration of field performance, structure, stratigraphy, and lithology. Directional equivalent fracture permeability, porosity, and matrix block dimensions are estimated using discrete fracture network (DFN) and 3D geologic models, while effective matrix permeability is derived using proprietary technology (patent...
We develop an ELLAM-MFEM approximation to the strongly coupled systems of time-dependent nonlinea... more We develop an ELLAM-MFEM approximation to the strongly coupled systems of time-dependent nonlinear partial differential equations (PDEs) and constraining equations, which describe fully miscible, highly compressible, multicomponent flows through heterogeneous and compressible porous media with singular sources and sinks. An Eulerian–Lagrangian localized adjoint method (ELLAM) is presented to solve the transport equations for concentrations. A mixed finite element method (MFEM) is used to solve the pressure PDE for the pressure and Darcy velocity simultaneously, which generates accurate fluid velocities and minimizes the numerical difficulties occurring in standard methods caused by differentiation of the pressure and then multiplication by rough coefficients. The ELLAM-MFEM solution technique symmetrizes and stabilizes the governing transport PDEs and greatly reduces nonphysical oscillation and/or excessive numerical dispersion present in many large-scale simulators. Computational experiments show that the ELLAM-MFEM solution technique can generate stable and physically reasonable numerical simulations even if coarse spatial grids and very large time steps are used.
Numerical simulation of uid ow in a hydrocarbon reservoir has to account for the presence of well... more Numerical simulation of uid ow in a hydrocarbon reservoir has to account for the presence of wells. The pressure of a grid cell containing a well is diierent from the average pressure in that cell and diierent from the bottomhole pressure for the well (Peaceman, 17]). This paper presents a study of grid pressures obtained from the simulation of single phase ow through an isotropic porous medium using diierent numerical methods. Well equations are proposed for Darcy ow with Galerkin nite elements and mixed nite elements. Furthermore, high velocity (non-Darcy) ow well equations are developed for cell-centered nite diierence, Galerkin nite element and mixed nite element techniques.
... Flaherty, Joseph E., Paslow, Pamela J., Shephard, Mark S., and Vasilakis, John D., Adaptive .... more ... Flaherty, Joseph E., Paslow, Pamela J., Shephard, Mark S., and Vasilakis, John D., Adaptive ... Annual ACM-SIAM Symposium on Discrete Algorithms (1998) DeSanto, John A., Mathematical ... for High-Performance Scientific Applications Andrew Cleary, Scott Kohn, Steven G. Smith ...
ABSTRACT We present an ELLAM-MFEM simulator for accurate, efficient, and robust simulations to hi... more ABSTRACT We present an ELLAM-MFEM simulator for accurate, efficient, and robust simulations to highly compressible flows in porous media with multiple wells. An Eulerian-Lagrangian localized adjoint method (ELLAM) is used to solve the advection-diffusion transport partial differential equation for concentration, while a mixed finite element method (MFEM) is used to solve the pressure equation for the pressure and mass flow rate. The ELLAM-MFEM simulator symmetrizes the transport equation, and eliminates nonphysical oscillation and/or excessive numerical dispersion in many large-scale simulators in industrial applications. Computational experiments show that the ELLAM-MFEM simulator can accurately simulate incompressible and compressible flows in porous media with multiple and different types of wells, large mobility ratios, discontinuous permeabilities and porosities, and anisotropic dispersion in tensor form, even if very large time steps and spatial grids are used.
An accurate and efficient simulator is developed for compressible flow porous media with wells. A... more An accurate and efficient simulator is developed for compressible flow porous media with wells. An Eulerian-Lagrangian localized adjoint method (ELLAM) is used to solve the transport partial differential equation for concentration, while a mixed finite element method (MFEM) is used to solve the pressure equation for the pressure and mass flow rate. The ELLAM-MFEM simulator symmetrizes the transport equation, eliminates nonphysical oscillation and/or excessive numerical dispersion in many large-scale simulators in industrial applications, and conserves mass. It minimizes the numerical difficulties occurring in standard methods caused by differentiation of the pressure and then multiplication by rough coefficients. Computational experiments show that the ELLAM-MFEM simulator can accurately simulate incompressible and compressible flows in porous media with wells, large mobility ratios, discontinuous permeabilities and porosities, and anisotropic dispersion in tensor form, even if very large time steps and spatial grids are used.
Model-Based Uncertainty Analysis (MBUA) is a method to evaluate reservoir performance uncertainty... more Model-Based Uncertainty Analysis (MBUA) is a method to evaluate reservoir performance uncertainty using multiple 3D models. Experimental Design techniques are used to determine what 3D models are built (unique geologic models which are then simulated) based on the number of identified uncertain factors. This method captures main effects and factor interactions and results in a multivariable response surface for each desired outcome (e.g. expected ultimate recovery, original hydrocarbon in place) which can be used for Monte Carlo simulations. The entire MBUA process results in tornado plots, exceedence curves, and a method to build representative models. A key strength of the MBUA process is the ability to capture dynamic responses such as water rate, production at early times, and plateau length. These responses provide project teams a greater understanding of how their subsurface uncertainties impact field performance and can help guide additional technical work, development planning decisions and representative model building. We have applied either a full or partial MBUA process to several fields for the purposes of identifying key technical uncertainties and improving the development plan across likely outcomes. Once an initial base case model has been built, subsequent models (totaling 16-54 models) can be rapidly built and simulated using normal geologic and flow simulation model workflows. While the analysis is quick, all model results are required to complete the analysis, thus simulation time is the biggest bottleneck in the process. Production data have been incorporated through either history-matching the initial base case or examining Monte Carlo simulation results for potential trends. The uncertainty analysis provides a streamlined process to examine potential uncertainty factors and allows a project to make informed decisions regarding future technical work or potential mitigation plans. A process overview will be presented along with sample results and lessons from completing the full MBUA.
Model-Based Uncertainty Analysis (MBUA) is a method to evaluate reservoir performance uncertainty... more Model-Based Uncertainty Analysis (MBUA) is a method to evaluate reservoir performance uncertainty using multiple 3D models. Experimental Design techniques are used to determine what 3D models are built (unique geologic models which are then simulated) based on the number of identified uncertain factors. This method captures main effects and factor interactions and results in a multivariable response surface for each desired outcome (e.g. expected ultimate recovery, original hydrocarbon in place) which can be used for Monte Carlo simulations. The entire MBUA process results in tornado plots, exceedence curves, and a method to build representative models. A key strength of the MBUA process is the ability to capture dynamic responses such as water rate, production at early times, and plateau length. These responses provide project teams a greater understanding of how their subsurface uncertainties impact field performance and can help guide additional technical work, development planni...
This paper describes the coupling of a pipeline network model to a reservoir simulator and its ap... more This paper describes the coupling of a pipeline network model to a reservoir simulator and its application to optimize the production strategy of two Mobil field developments. Mobil`s PEGASUS simulator is an integrated, all-purpose reservoir simulator that handles black-oil, compositional, faulted, and naturally fractured reservoirs. The authors have extended the simulator to allow simultaneous modeling of multiple reservoirs coupled with
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