A Fully Implicit, Parallel Compositional Simulator (GPAS)

The objective of this research is to develop a general-purpose adaptive reservoir simulator (GPAS) for parallel supercomputers and clusters of PCs. The simulator is designed to perform accurate, efficient high-resolution simulations of fluid flow in permeable media for large complex problems. An important aspect of this project is the development of a reservoir simulator capable of modeling variety of oil recovery processes with multi-million gridblock resolutions.

The initial development was for a compositional miscible gas flooding process. Additional modules implemented are:

  • Chemical module for surfactant/polymer flooding
  • Dual porosity for EOR processes in naturally fractured reservoirs
  • Geomechanics module to model the rock properties such as permeability and porosity due to rock stress changes by field injection and production activities
  • Thermal module for steam flooding and other thermal methods

[Schematic diagram of GPAS modules.]

Current research activities include:

  • Full coupling of EOS gas and chemical phase behavior models
  • Unstructured grid implementation using element-based finite volume method with mixed elements
  • Development of a wellbore module and a coupled wellbore module
  • Development of discrete fracture module
  • Development of wettability alteration model
  • Comparison of several solvers for parallel processing
  • Implementation and comparison of various formaulations based on selection of primary variables