High energy geothermal simulations in faulted reservoirs with code ComPASS
 Team: this project started in 2014 in collaboration between
 BRGM: Simon Lopez and Farid Smai
 Joint INRIALJAD team Coffee: Feng Xing, Laurence Beaude, Konstantin Brenner and Roland Masson
 The ANR project CHARMS started in october 2016 for 4 years strenghens the project and enlarges
it to the additional partners Storengy (Delphine Patriarche, Vincent Seignole, JeanFrédéric Thébault), La Maison de la Simulation (Michel Kern, Julien Bigot, Pascal Tremblin, Thomas Dufaut) and the Laboratoire Jacques Louis Lions (Cindy Guichard, Robert Eymard).

Objectives: our objectives are to develop efficient parallel numerical methods to simulate gas liquid compositional thermal
flow in high energy geothermal reservoirs.
The spatial discretization is adapted to unstructured polyhedral meshes and takes into account discrete fracture
or fault networks represented as 2D surfaces connected to the surrounding 3D heterogeneous anisotropic
porous medium (the matrix).
The difficulties result from the highly contrasted spatial and temporal scales
and petrophysical properties between the 3D matrix and the fault network.
The second difficulty is to account for the strong couplings and high nonlinearities induced by the large range of pressure and temperature and by the phase appearance and disapearance.
These numerical methods and physical models are implemented in code ComPASS (Computing Architecture to Speed up Simulation).
 Brief history of the code ComPASS
 Current version of ComPASS: it has the following features
 Computer science
 Version management of the code using Inria GitLab
 SPMD Paradigm
 Fortran 2003 + C/C++ + MPI
 Parallelism based on a partitioning of the mesh with Metis
 One layer of ghost cells
 Connected to the solver libraries Petsc + Hypre + Trilinos
 Visualization ouputs using parallel vtk format
 Checkpointing using HDF5
 High level python API (in development)
 Numerical methods
 Physics
 Multiphase compositional thermal Darcy flow model
 2D discrete fracture or fault network coupled with the surrounding 3D matrix
 Multibranch well model (in development)
Thermal convection
 Gas liquid thermal model with a single component H2O
 Reservoir of size 3kmx3kmx3km initially at hydrostatic pressure and 300 K (liquid phase)
 Temperature fixed to 600 K at the bottom boundary (liquid phase) and to 300 K at the top boundary
 Homogeneous porous medium
 3D Cartesian mesh of size 100x100x100
 15000 days of simulation
 Temperature and gas saturation function of time
Thermal convection with four fractures
 Gas liquid thermal model with a single component H2O
 Reservoir of size 3kmx3kmx3km initially at hydrostatic pressure and 300 K (liquid phase)
 Temperature fixed to 600 K at the bottom boundary (liquid phase) and to 300 K at the top boundary
 Homogeneous matrix of permeability 1 mDarcy with four fractures of width 1 m and permeability 1 Darcy
 3D Cartesian mesh of size 240x240x240
 220000 days of simulation
 Temperature and gas saturation in the matrix and in the fractures function of time
Liquid gas thermal simulation with a large discrete fracture network
 Gas liquid thermal model with a single component H2O
 Reservoir of size 6kmx3kmx250m with roughly 1000 fractures of width 1 m
 Permeability ratio between the fracture network and the matrix of 1000
 3D Mesh with 1.000.000 prismatic cells
 Reservoir initially at 450 K and 1 MPa (liquid phase)
 Left output boundary at 450 K and 1 MPa (liquid phase) and right input boundary at 550K and 2 Mpa (gas phase)
 Gas saturation and Temperature in the matrix and fracture network function of time
 Speed up
Tracer simulation with a large discrete fracture network
 Reservoir of size 6kmx3kmx250m with roughly 1000 fractures of width 1 m
 Ratio of permeability between the fractures and the matrix of 10000
 3D Mesh with 10.000.0000 prismatic cells
 Flow and tracer simulation
 One injection well and two producers (see below)
 8 years of simulation
 Prismatic mesh of the matrix and triangular mesh of the fracture network
 Tracer in the matrix and in the fracture network at the end of the simulation
 Pressure field and tracer production at both wells
 Speed up
Oil migration in a fractured reservoir with HC dissolution in the water phase
 Two phases water and oil and two components H2O and HC
 Dissolution of the HC component in the water phase
 Reservoir of size 100 mx 100 mx 100m with fractures of width 1 cm
 Permeability ratio between the fracture network and the matrix of 10000
 3D Mesh with 6.000.000 tetrahedra
 Reservoir initially saturated with pure water and injection of oil from the bottom boundary with a gravity dominant flow
 10000 days of simulation
 Oil saturation and molar fraction of HC in the water phase both in the matrix and the fracture network function of time
 Speed up
Updated 04022018