Coupling LaGrit unstructured mesh generation and model setup with TOUGH2 flow and transport: A case study

Journal Article · Thu Jun 15 00:00:00 EDT 2017 · Computers and Geosciences

DOI:https://doi.org/10.1016/j.cageo.2017.06.012· OSTI ID:1369178

Sentis, Manuel Lorenzo ^[1]; Gable, Carl W. ^[2]

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1. Swiss Federal Nuclear Safety Inspectorate, ENSI (Switzerland)
2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Furthermore, there are many applications in science and engineering modeling where an accurate representation of a complex model geometry in the form of a mesh is important. In applications of flow and transport in subsurface porous media, this is manifest in models that must capture complex geologic stratigraphy, structure (faults, folds, erosion, deposition) and infrastructure (tunnels, boreholes, excavations). Model setup, defined as the activities of geometry definition, mesh generation (creation, optimization, modification, refine, de-refine, smooth), assigning material properties, initial conditions and boundary conditions requires specialized software tools to automate and streamline the process. In addition, some model setup tools will provide more utility if they are designed to interface with and meet the needs of a particular flow and transport software suite. A control volume discretization that uses a two point flux approximation is for example most accurate when the underlying control volumes are 2D or 3D Voronoi tessellations. In this paper we will present the coupling of LaGriT, a mesh generation and model setup software suite and TOUGH2 to model subsurface flow problems and we show an example of how LaGriT can be used as a model setup tool for the generation of a Voronoi mesh for the simulation program TOUGH2. To generate the MESH file for TOUGH2 from the LaGriT output a standalone module Lagrit2Tough2 was developed, which is presented here and will be included in a future release of LaGriT. Here in this paper an alternative method to generate a Voronoi mesh for TOUGH2 with LaGriT is presented and thanks to the modular and command based structure of LaGriT this method is well suited to generating a mesh for complex models.

• Research Organization: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: USDOE Office of Civilian Radioactive Waste Management (RW)
• Grant/Contract Number: AC52-06NA25396; 230357
• OSTI ID: 1369178
• Report Number(s): LA-UR-17-25234
• Journal Information: Computers and Geosciences, Vol. 108, Issue C; ISSN 0098-3004
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
Earth Sciences
Unstructured mesh
Mesh generation
Finite-volume method
Integrated finite differences
Voronoi tessellation
Model setup
LaGriT
TOUGH2
FORGE
Waste geological repository
Gas pressure