CMWRXVI
ALLIANCES : SIMULATION PLATFORM FOR
RADIOACTIVE WASTE DISPOSAL
MONTARNAL PH.1,*, BENGAOUER A.1, LOTH L. 2, CHAVANT C. 3
1
CEA Saclay DANS/DM2S/SFME/MTMS, 91191 Gif sur Yvette, France
2
ANDRA DS/CS, 1-7 rue Jean Monnet, 92298 Châtenay-Malabry Cedex, France
3
EDF R&D, 1 av. du G. de Gaulle, 92141 Clamart, France
ABSTRACT
CEA, ANDRA and EDF are jointly developing the software platform Alliances whose
aim is to produce a tool for the simulation of nuclear waste storage and disposal. This type of
simulations deals with highly coupled thermo-hydro-mechanical-chemical and radioactive (T-
H-M-C-R) processes. Alliances aim is not to develop a new scientific calculation code but to
accumulate within the same simulation environment the already acquired knowledge and to
gradually integrate new knowledge. The release 1 of Alliances was distributed to users in
December 2003. The next releases of Alliances (2.x) include more physical phenomena like
reactive transport in unsaturated flow, thermal and mechanical models and their coupling with
hydraulics and alteration of waste package coupled with the environment. Beyond, his first
application domain for high level nuclear waste disposal, Alliances can be used for a large
range of computations in the field of porous media simulation.
1. INTRODUCTION
The safety assessment of nuclear waste disposals needs to predict coupled thermo-hydro-
mechanical-chemical and radioactive (T-H-M-C-R) processes, involving phenomena such as
heat generation and transport (due to radioactive decay of nuclear waste), infiltration of
groundwater (hydrological processes), swelling pressure of buffer material due to saturation
(mechanical processes) and chemical evolution of buffer material and porewater (chemical
processes). It appeared as necessary to develop and assess numerical tools that model these
physical mechanisms.
Therefore, the French Atomic Energy Commission (CEA), and the French Agency for
Radioactive Waste Management (ANDRA) have been jointly developing since 2001 the
software platform Alliances. The French Electric company (EDF) joined the project in 2003.
The aim of the project is to obtain a numerical platform enabling the simulation of all
phenomena governing storage and disposal safety with the following characteristics: (i)
Efficient coupling of different numerical codes; (ii) Simulation of multi-physical and multi-
scale phenomena; (iii) Uncertainties analysis related to data and models; (iv) Studies
management and traceability.
More precisely, the physical models currently implemented are: flow in unsaturated and
saturated porous media, radionuclide transport in unsaturated/saturated media,
*
Corresponding author :
. 1
, Ph. Montarnal, A. Bengaouer, L. Loth, C. Chavant
chemistry/Transport coupling in saturated media with feedback of porosity changes on
transport properties, thermo-hydraulic and mechanical coupled processes (THM), thermo-
aerolics, alteration of waste packages and their interaction with its environment.
The next releases of Alliances will include more physical phenomena: mainly reactive
transport in multiphase flows to take into account gas migration.
These models lead to a large set of non-linear differential equations that can be solved on
3D meshing by using finite element like methods. Main numerical components currently
integrated in Alliances use a scalar architecture. Current works are done on massively
parallels architecture which will available in the next release of Alliances.
Alliances goal is not to develop a new scientific tool but to accumulate within the same
simulation environment the already acquired knowledge and to gradually integrate new ones.
Therefore, it is based on the following three fundamental choices:
- Seamless integration of legacy codes as software components ;
- Allow efficient coupling between components by sharing a common data model for
mesh and field;
- Sharing Salome (www.salome-platform.org) open source components for pre and post
processing.
Special attention is paid to the qualification and validation program. It proceeds by tests
with a gradual complexity: first comparing calculations to analytical solutions, then defining
benchmark exercises between codes implemented in the platform and external ones. The tests
validate the different aspects of the application validity domain of the modules. For each test,
several options are tested: selected codes, size of the grid, methods of discretization (Finite
Volume, Mixed Hybrids Finite elements...), linear solver. The tests are included in a non
regression test suite.
ANDRA safety studies were done with the platform during 2004-2005. Several
computations were also carried out at CEA mainly on reactive transport simulations.
Alliances is currently available on PC/Linux computer system and on the CEA
supercomputer facilities CCRT.
Specific accommodation could be established for a free utilisation of Alliances for
research applications (contact the corresponding author)
This paper is organized as follows. Section 2 is devoted to the software architecture and
coupling methodology. The Alliances capabilities are described in section 3. Some
applications are presented in section 4. Finally we give a conclusion and prospects for further
work.
2
ALLIANCES : SIMULATION PLATFORM FOR
RADIOACTIVE WASTE DISPOSAL
MONTARNAL PH.1,*, BENGAOUER A.1, LOTH L. 2, CHAVANT C. 3
1
CEA Saclay DANS/DM2S/SFME/MTMS, 91191 Gif sur Yvette, France
2
ANDRA DS/CS, 1-7 rue Jean Monnet, 92298 Châtenay-Malabry Cedex, France
3
EDF R&D, 1 av. du G. de Gaulle, 92141 Clamart, France
ABSTRACT
CEA, ANDRA and EDF are jointly developing the software platform Alliances whose
aim is to produce a tool for the simulation of nuclear waste storage and disposal. This type of
simulations deals with highly coupled thermo-hydro-mechanical-chemical and radioactive (T-
H-M-C-R) processes. Alliances aim is not to develop a new scientific calculation code but to
accumulate within the same simulation environment the already acquired knowledge and to
gradually integrate new knowledge. The release 1 of Alliances was distributed to users in
December 2003. The next releases of Alliances (2.x) include more physical phenomena like
reactive transport in unsaturated flow, thermal and mechanical models and their coupling with
hydraulics and alteration of waste package coupled with the environment. Beyond, his first
application domain for high level nuclear waste disposal, Alliances can be used for a large
range of computations in the field of porous media simulation.
1. INTRODUCTION
The safety assessment of nuclear waste disposals needs to predict coupled thermo-hydro-
mechanical-chemical and radioactive (T-H-M-C-R) processes, involving phenomena such as
heat generation and transport (due to radioactive decay of nuclear waste), infiltration of
groundwater (hydrological processes), swelling pressure of buffer material due to saturation
(mechanical processes) and chemical evolution of buffer material and porewater (chemical
processes). It appeared as necessary to develop and assess numerical tools that model these
physical mechanisms.
Therefore, the French Atomic Energy Commission (CEA), and the French Agency for
Radioactive Waste Management (ANDRA) have been jointly developing since 2001 the
software platform Alliances. The French Electric company (EDF) joined the project in 2003.
The aim of the project is to obtain a numerical platform enabling the simulation of all
phenomena governing storage and disposal safety with the following characteristics: (i)
Efficient coupling of different numerical codes; (ii) Simulation of multi-physical and multi-
scale phenomena; (iii) Uncertainties analysis related to data and models; (iv) Studies
management and traceability.
More precisely, the physical models currently implemented are: flow in unsaturated and
saturated porous media, radionuclide transport in unsaturated/saturated media,
*
Corresponding author :
. 1
, Ph. Montarnal, A. Bengaouer, L. Loth, C. Chavant
chemistry/Transport coupling in saturated media with feedback of porosity changes on
transport properties, thermo-hydraulic and mechanical coupled processes (THM), thermo-
aerolics, alteration of waste packages and their interaction with its environment.
The next releases of Alliances will include more physical phenomena: mainly reactive
transport in multiphase flows to take into account gas migration.
These models lead to a large set of non-linear differential equations that can be solved on
3D meshing by using finite element like methods. Main numerical components currently
integrated in Alliances use a scalar architecture. Current works are done on massively
parallels architecture which will available in the next release of Alliances.
Alliances goal is not to develop a new scientific tool but to accumulate within the same
simulation environment the already acquired knowledge and to gradually integrate new ones.
Therefore, it is based on the following three fundamental choices:
- Seamless integration of legacy codes as software components ;
- Allow efficient coupling between components by sharing a common data model for
mesh and field;
- Sharing Salome (www.salome-platform.org) open source components for pre and post
processing.
Special attention is paid to the qualification and validation program. It proceeds by tests
with a gradual complexity: first comparing calculations to analytical solutions, then defining
benchmark exercises between codes implemented in the platform and external ones. The tests
validate the different aspects of the application validity domain of the modules. For each test,
several options are tested: selected codes, size of the grid, methods of discretization (Finite
Volume, Mixed Hybrids Finite elements...), linear solver. The tests are included in a non
regression test suite.
ANDRA safety studies were done with the platform during 2004-2005. Several
computations were also carried out at CEA mainly on reactive transport simulations.
Alliances is currently available on PC/Linux computer system and on the CEA
supercomputer facilities CCRT.
Specific accommodation could be established for a free utilisation of Alliances for
research applications (contact the corresponding author)
This paper is organized as follows. Section 2 is devoted to the software architecture and
coupling methodology. The Alliances capabilities are described in section 3. Some
applications are presented in section 4. Finally we give a conclusion and prospects for further
work.
2
