Finite Element Heat and Mass Transfer Code (FEHM)
The numerical background of the FEHM computer code can be traced to the early 1970s when it was used to simulate geothermal and hot dry rock reservoirs. The primary use over a number of years was to assist in the understanding of flow fields and mass transport in the saturated and unsaturated zones below the potential Yucca Mountain repository. Today FEHM is used to simulate groundwater and contaminant flow and transport in deep and shallow, fractured and un-fractured porous media throughout the US DOE complex. FEHM has proved to be a valuable asset on a variety of projects of national interest including Environmental Remediation of the Nevada Test Site, the LANL Groundwater Protection Program, geologic CO2 sequestration, Enhanced Geothermal Energy (EGS) programs, Oil and Gas production, Nuclear Waste Isolation, and Arctic Permafrost.
• 3-dimensional complex geometries with unstructured grids
These documents are downloadable pdf files and can be viewed and printed using a PDF reader such as Adobe Reader. The FEHM User Manual details how to use the FEHM application and is based on V3 release. Supplemental updates to selected macro control statements are documented in the User Manual Appendix."User Manual for FEHM Application V3 and Supplemental Appendices "
In the following documents, Models and Methods provides numerical details for the FEHM code, and the Validation & Verification (V&V) document describe the Test Suites distributed with the FEHM executable.
"Models and Methods Summary for the FEHM Application"
"V&V Test Suite for the FEHM Application"
"FEHM: A control volume finite element code for simulating subsurface multi-phase multi-fluid heat and mass transfer" 2007 LA-UR-3359, George A. Zyvoloski
FEHM Code Development Team
For help or suggestions you may contact a team member directly, or use our
• George A. Zyvoloski, FEHM Team Leader (Retired), firstname.lastname@example.org
FEHM is available on Linux, MacOSX and WINDOWS. Executables of FEHM are available at no cost.
Register as a FEHM user here.
Copyright 2013. Los Alamos National Security, LLC for FEHM LA-CC-2012-083. This material was produced under U.S. Government contract DE-AC52-06NA25396 for Los Alamos National Laboratory (LANL), which is operated by Los Alamos National Security, LLC for the U.S. Department of Energy. The U.S. Government has rights to use, reproduce, and distribute this software. Neither the U.S. Government nor Los Alamos National Security, LLC or persons acting on their behalf, make any warranty, express or implied, or assumes any liability for the accuracy, completeness, or usefulness of the software, any information pertaining to the software, or represents that its use would not infringe privately owned rights.
Distribution of FEHM source code is limited to FEHM team collaborators with a LANS approved and signed Contributor Agreement. Contact Terry Miller email@example.com or an FEHM team member for more information.
Auxiliary FEHM Programs
Fehmpytests is a new test suite for FEHM developers to easily test new code and add
new tests for existing or future functionality. Fehmpytests uses the Python unittest module and
a general test method that can be called for each new test case.
Future plans are to integrate Fehmpytests into the FEHM build and version control process.
is an open-source (LGPL 2.1) Python library that provides classes and methods to support a scripting environment for the subsurface heat and mass transfer, and geomechanics code FEHM. It is inspired by a similar library, PyTOUGH, available for use with the TOUGH2 family of codes.
• WALKABOUT: performs random walk particle tracking simulations of solute transport based on groundwater flow solutions from FEHM. A typical workflow for Walkabout within the FEHM system would use LaGrit to generate unstructured grids. FEHM then provides a discretized representation of the steady-state flow field to Walkabout. Given this discrete solution, Walkabout then reconstructs a groundwater flow field, and performs the random walk particle tracking calculation.
Auxiliary Grid-Generating Programs
LaGriT Grid Generation ToolBox is
LANL authored Mesh generation software for geological applications. LaGriT writes mesh and model setup files appropriate for use by FEHM. LaGriT Meshing for geologic applications can be found on the project pages,
Auxiliary Grid Viewing Programs
• GMV, General Mesh Viewer is an easy to use, 3-D scientific visualization tool designed to view simulation data from any type of structured or unstructured mesh.