Los Alamos Grid Toolbox

LaGriT: A Versatile Mesh Generation and Optimization Toolbox

LaGriT provides robust mesh generation, optimization, and maintenance for geological modeling, while its flexible tools support applications beyond earth sciences.

LaGriT (Los Alamos Grid Toolbox) is a library of tools designed for creating, optimizing, and managing meshes in two and three dimensions. Originally tailored for geology and geophysics modeling, LaGriT is versatile enough for applications in porous flow modeling, finite element analysis of fault systems, seismology, and even simulations of asteroids and hydrothermal systems.

While LaGriT is widely used in earth sciences, its adaptable functions make it suitable for any field requiring mesh structures, material property assignments, and boundary condition setups. Beyond model creation, LaGriT also supports data preprocessing and analysis of mesh and vertex-based datasets, enabling researchers to refine and examine complex simulations with ease.

Capabilities

Representation of 2- and 3-dimensional complex geometries
Unstructured triangle/tetrahedral and structured or unstructured quadrilateral/hexahedral meshing
Model set-up including assigning material properties, boundary conditions, and initial conditions
Adaptive mesh refinement, smoothing, and optimization
2D and 3D Delaunay triangulation conforming to complex geometry
Output for solver packages including specialized format for FEHM, Amanzi/ATS, PFLOTRAN, and TOUGH2
Interactive command line, batch input file, or embedded in Fortran/C interfaces (no GUI)

LaGrit is Availible on GitHub

Open source code

Go to GitHub

Documentation

Auxiliary LaGriT Programs

PyLaGrit: Scripted LaGrit Interface

The PyLaGriT module allows LaGriT commands to be accessed interactively and in batch mode from Python. Common and useful meshing workflows are combined into a set of higer level python calls which also enables loops and better parameter control.

VORONOI: Tesselation Control Volumes

VORONOI is a parallel and scalable program for writing Voronoi tessellation control volumes (connectivity graph, control volume areas/volumes) compatible with: FEHM, PFLOTRAN, TOUGH2, and HDF5. The Voronoi software requires a PETsc library.

GRIDDER: Rectangular Grid Generator

GRIDDER: is rectangular grid generator that creates structured grids in a format used by FEHM.

Visualization Software

Software often used with LaGriT input and output files include:

ParaView
VISIT
Tecplot
AVS (Advanced Visual Systems)
GMV (General Mesh Viewer)

LaGriT Applications

dfnWorks: Discrete Fracture Network Workflow

dfnWorks is a parallelized computational suite to generate three-dimensional discrete fracture networks (DFN) and simulate flow and transport. dfnWorks creates high-fidelity three-dimensional networks dfnGen, which combine FRAM (the feature rejection algorithm for meshing) methodology to stochastically generate three-dimensional DFNs with the LaGriT meshing toolbox to create a high-quality computational mesh representation.

TINerator: Python/GIS Workflow for stacked Triangulations

TINerator takes advantage of LaGriT mesh commands combined with GIS data to triangulate and stack a 3D mesh.

Meshing: Team Projects

Gallery of selected meshing project images.
SFWD-GDSA Geologic Applications Project and workflow web pages
Examples for GDSA Geologic Applications GitHub repo.
VoroCrust collaboration with Sandia GitHub repo.