FEHM
Encyclopedia
FEHM is a groundwater model
that has been developed in the Earth and Environmental Sciences Division at Los Alamos National Laboratory
over the past 30 years. The executable is available free at the FEHM Website. The capabilities of the code have expanded over the years to include multiphase flow of heat and mass with air, water, and CO2, methane hydrate, plus multi-component reactive chemistry and both thermal and mechanical stress. Applications of this code include simulations of: flow and transport in basin scale groundwater systems
, migration of environmental isotopes
in the vadose zone
, geologic carbon sequestration, oil shale
extraction, geothermal energy, migration of both nuclear and chemical contaminants, methane hydrate formation, seafloor hydrothermal circulation
, and formation of karst
. The simulator has been used to generate results for more than 100 peer reviewed publications which can be found at FEHM Publications.
Groundwater model
Groundwater models are computer models of groundwater flow systems, and are used by hydrogeologists. Groundwater models are used to simulate and predict aquifer conditions.-Characteristics:...
that has been developed in the Earth and Environmental Sciences Division at Los Alamos National Laboratory
Los Alamos National Laboratory
Los Alamos National Laboratory is a United States Department of Energy national laboratory, managed and operated by Los Alamos National Security , located in Los Alamos, New Mexico...
over the past 30 years. The executable is available free at the FEHM Website. The capabilities of the code have expanded over the years to include multiphase flow of heat and mass with air, water, and CO2, methane hydrate, plus multi-component reactive chemistry and both thermal and mechanical stress. Applications of this code include simulations of: flow and transport in basin scale groundwater systems
, migration of environmental isotopes
Environmental isotopes
The environmental isotopes are a subset of the isotopes, both stable and radioactive, which are the object of Isotope geochemistry.The most used environmental isotopes are:* deuterium* tritium* carbon-13* carbon-14* nitrogen-15* oxygen-18...
in the vadose zone
Vadose zone
The vadose zone, also termed the unsaturated zone, is the portion of Earth between the land surface and the top of the phreatic zone i.e. the position at which the groundwater is at atmospheric pressure . Hence the vadose zone extends from the top of the ground surface to the water table...
, geologic carbon sequestration, oil shale
Oil shale
Oil shale, an organic-rich fine-grained sedimentary rock, contains significant amounts of kerogen from which liquid hydrocarbons called shale oil can be produced...
extraction, geothermal energy, migration of both nuclear and chemical contaminants, methane hydrate formation, seafloor hydrothermal circulation
Hydrothermal circulation
Hydrothermal circulation in its most general sense is the circulation of hot water; 'hydros' in the Greek meaning water and 'thermos' meaning heat. Hydrothermal circulation occurs most often in the vicinity of sources of heat within the Earth's crust...
, and formation of karst
KARST
Kilometer-square Area Radio Synthesis Telescope is a Chinese telescope project to which FAST is a forerunner. KARST is a set of large spherical reflectors on karst landforms, which are bowlshaped limestone sinkholes named after the Kras region in Slovenia and Northern Italy. It will consist of...
. The simulator has been used to generate results for more than 100 peer reviewed publications which can be found at FEHM Publications.
Abstract
The Subsurface Flow and Transport Team at the Los Alamos National Laboratory (LANL) has been involved in large scale projects including performance assessment of Yucca Mountain, Environmental Remediation of the Nevada Test Site, the LANL Groundwater Protection Program and geologic CO2 sequestration. Subsurface physics has ranged from single fluid/single phase fluid flow when simulating basin scale groundwater aquifers to multi-fluid/multi-phase fluid flow when simulating the movement of air and water (with boiling and condensing) in the unsaturated zone surrounding a potential nuclear waste storage facility. These and other projects have motivated the development of software to assist in both scientific discovery and technical evaluation. LANL’s FEHM (Finite Element Heat and Mass) computer code simulates complex coupled subsurface processes as well flow in large and geologically complex basins. Its development has spanned several decades; a time over which the art and science of subsurface flow and transport simulation has dramatically evolved. For most early researchers, models were used primarily as tools for understanding subsurface processes. Subsequently, in addition to addressing purely scientific questions, models were used in technical evaluation roles. Advanced model analysis requires a detailed understanding of model errors (numerical dispersion and truncation) as well as those associated with the application (conceptual and calibration) Application errors are evaluated through exploration of model and parameter sensitivities and uncertainties. The development of FEHM has been motivated subsurface physics of applications and also by the requirements of model calibration, uncertainty quantification, and error analysis. FEHM possesses unique features and capabilities that are of general interest to the subsurface flow and transport community and it is well suited to hydrology, geothermal, petroleum reservoir applications, and CO2 sequestration.External links
More information on this versatile model can be found at:See also
- AquiferAquiferAn aquifer is a wet underground layer of water-bearing permeable rock or unconsolidated materials from which groundwater can be usefully extracted using a water well. The study of water flow in aquifers and the characterization of aquifers is called hydrogeology...
- HydrogeologyHydrogeologyHydrogeology is the area of geology that deals with the distribution and movement of groundwater in the soil and rocks of the Earth's crust, . The term geohydrology is often used interchangeably...
- GroundwaterGroundwaterGroundwater is water located beneath the ground surface in soil pore spaces and in the fractures of rock formations. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water. The depth at which soil pore spaces or fractures and voids in rock...
- Groundwater flow equationGroundwater flow equationUsed in hydrogeology, the groundwater flow equation is the mathematical relationship which is used to describe the flow of groundwater through an aquifer. The transient flow of groundwater is described by a form of the diffusion equation, similar to that used in heat transfer to describe the flow...
- Groundwater energy balanceGroundwater energy balanceThe groundwater energy balance is the energy balance of a groundwater body in terms of incoming hydraulic energy associated with groundwater inflow into the body, energy associated with the outflow, energy conversion into heat due to friction of flow, and the resulting change of energy status and...
- Watertable controlWatertable controlWatertable control is the practice of controlling the water table in agricultural land by subsurface drainage with proper criteria to improve the crop production.- Description and definitions :...
- Groundwater drainage by wellsWell drainageWell drainage means drainage of agricultural lands by wells. Agricultural land is drained by pumped wells to improve the soils by controlling water table levels and soil salinity.-Introduction:...
- Salinity model