A New Generation Framework for Petroleum Reservoir Simulation

As part of the ACTI project, we have developed a simulator framework IPARS (Integrated Parallel Accurate Reservoir Simulator) to serve as a test-bed for multiphase flow models, numerical discretizations, solvers, and upscaling.

General geometry on IPARS:


Dipping Reservoir



Small Angle Approximation

Small Angle Approximation

IPARS Collaborators:

  • John Wheeler
  • Mary Wheeler
  • Krzysztof Banas
  • Steve Bryant
  • Srinivas Chippada
  • Joe Eaton
  • Carter Edwards
  • Xiuli Gai
  • Sebastien Lacroix
  • Wonsuck Lee
  • Qin Lu
  • Bahareh Momken
  • Myeong-Hwan Noh
  • Manish Parashar
  • Victor Parr
  • Malgorzata Peszynska
  • Philippe Quandalle
  • Beatríce Rivière
  • Kamy Sephernoori
  • Yuri Vassilevski
  • Peng Wang
  • Ivan Yotov

IPARS Users online help

Current Features

  • Portability between different platforms including PC under DOS/Windows or Linux and PC clusters, RS6K and SP2, SGI, Cray T3E, etc.
  • Memory management for multiple fault blocks, multiblock nonmatching grids and general geometry.
  • Multiple processors (ghost region updates and global reduce operations)
  • Time step control
  • Error management, CPU timing system
  • Keyword input
  • Visualization output for scalar and vector variables, data tables etc.
  • A suite of linear solvers
  • Well management tools for different types of injection and production wells
  • Multiple physical models including
    • Two phase (oil/water) implicit,
    • Two phase (oil/water) sequential (Fast Accurate),
    • Black oil (three phase, three component),
    • Two phase (air/water) implicit,
    • Single phase (slightly compressible) explicit,
    • Single phase (slightly compressible) implicit,
    • EOS compositional (in review phase, also see EOS page),
    • And much more (some still in development phase)…
  • Multiblock formulation using mortar spaces and implemented with MACE
  • Multimodel formulation allowing for multinumerics and multiphysics

Recent Accomplishments

  • We are now running Mega-size problems with the two-phase and black oil models on our PC-clusters. The parallel scaling of the code is very good.
  • We have recently achieved multiphysics; coupling in which IPARS models: black oil, two phase and single phase models are coupled across interface. In the earlier phase of this work, we completed multinumerics coupling.
  • IPARS black oil model was succesfully used in the projects:
    • Coupling of multiphase flow with geomechanics, in collaboration with Sandia National Labs, see Coupled Geomechanical Deformation and Reservoir Simulation , or here.
    • Coupling of multiphase flow with single-well injectivity modeling.
  • Advances in parallel procedures for multiphase flow include preconditioned GMRES with variable multistage preconditioners (Uzawa, and IMPES family). These schemes have been tested in the IPARS framework for two and three phase fully-implicit models, and are the foundation of the excellent parallel scalability of IPARS. Collaboration with Philippe Quandalle (IFP) and Yuri Vassilevski (Russian Academy of Sciences) was crucial to achieving the current level of performance.
  • Collaboration with ICES (Institute for Computational Engineering and Sciences) at UT has raised interesting possibilities for applying recent computer science advances, such as coupling the low level dynamic mesh data structures of the DAGH (Distributed Adaptive Grid Hierarchy) package with the domain knowledge framework embodied in IPARS, and using “space-filling curves” for ordering the grid elements upon the processors.

Current features in detail:

Recent accomplishments in detail:

  • Mega-size problems
  • Parallel scaling of the code
  • Multiphysics coupling
  • Multinumerics coupling
  • Coupled Geomechanical Deformation and Reservoir Simulation
  • Coupling of multiphase flow with single-well injectivity modeling

Related Presentations

  • Physical and computational domain decompositions for multiphysics, multiphase, and multiscale porous media problems
  • “Computational Challenges in Reservoir Simulation”