Section: New Software and Platforms

Hydrogeology

GRT3D

Participants : Édouard Canot, Jocelyne Erhel [correspondant] .

• Version: version 2.0, April 2014

• APP: registered

• Programming language: C

• Abstract: Reactive transport modeling has become an essential tool for understanding complex environmental problems. It is an important issue for MoMaS and C2S@EXA partners (see sections 8.2.5 , 8.2.3 ), in particular Andra. We have developed a method coupling transport and chemistry, based on a method of lines such that spatial discretization leads to a semi-discrete system of algebraic differential equations (DAE system). The main advantage is to use a complex DAE solver, which controls simultaneously the timestep and the convergence of Newton algorithm. The approach SIA uses a fixed-point method to solve the nonlinear system at each timestep, whereas the approach SNIA uses an explicit scheme.

  The software suite GRT3D has four executable modules:

  • SIA1D: Sequential Iterative Approach for 1D domains;

  • GDAE1D: Global DAE approach for 1D domains;

  • SNIA3D: Sequential Non Iterative Approach for 1D, 2D or 3D domains.

  • GDAE3D: Global DAE approach for 1D, 2D or 3D domains. This module has three variants: the original one with logarithms, an optimized one still with logarithms, an optimized one which does not use logarithms.

• Current work: extension of the chemistry module and parallelization.

SBM

Participant : Géraldine Pichot [correspondant] .

• Version: version 1.0, November 2013

• Programming language: C

• Abstract: SBM (Skew Brownian Motion) is a code developed with A. Lejay (Inria, Nancy). This code allows exact or approximated simulations of the Skew Brownian Motion. This code is used for the simulation, with a Monte-Carlo approach, of a 1D diffusion process with a discontinuous diffusion coefficient. Several benchmark tests are also implemented.

• Current work: paper about benchmarking results 5.2.2 .

GENFIELD

Participants : Jean-Raynald de Dreuzy, Jocelyne Erhel, Grégoire Lecourt, Géraldine Pichot [correspondant] .

• Version: version 1.0, December 2014

• Programming language: C++

• Abstract: GENFIELD allows the generation of log-normal correlated fields. It is based on a spectral method and uses the FFTW library. Parallelism is implemented using MPI communications. GENFIELD is used in hydrogeology to model natural fields, like hydraulic conductivity or porosity fields.

• Current work: paper about algorithms 6.4.7 .