NASA Home Page Goddard Space Flight Center Home Page
NASA Logo - Goddard Space Flight Center   + Visit
a directory of Earth science data and services Global Change Master Directory Web site
header 2 bullet Links bullet FAQ bullet Contact Us bullet Site Map
Home Data Sets Data Services Learn about GCMD_legacy's portal collaborations. Add new dataset or dataservice records to GCMD_legacy What's New Participate Calendar About GCMD_legacy
Record Search Query: ServiceParameters>MODELS>COMPONENT PROCESS MODELS

VS2DI - A graphical software package for simulating fluid flow and solute or energy transport in variably saturated porous media
[ Get Service ]
[ Update this Record ]

Abstract: VS2DI is a graphical software package for simulating flow and
transport in variably saturated porous media. This software package
consists of three components:

- VS2DTI, for simulating fluid flow and solute transport,
- VS2DHI, for simulating fluid flow and energy (heat) transport,
- a standalone postprocessor, for viewing results saved from
previous simulation runs.

Both VS2DTI and VS2DHI combine a graphical user interface with a
numerical model to create an integrated, window-based modeling
environment. Users can easily specify or change the model domain,
hydraulic and transport properties, initial and boundary conditions,
grid spacing, and other model parameters. Simulation results can be
displayed as contours of pressure head, moisture content,
saturation, concentration or temperature, and velocity or flux for
each time step, thus creating a simple animation.

The numerical models used for flow and transport calculations are
the U.S. Geological Survey's computer models VS2DT (for solute
transport) and VS2DH (for energy transport). VS2DT is a finite-
difference model that solves Richard's equation for fluid flow, and
the advection-dispersion equation for solute transport. The model
can analyze problems in one or two dimensions using either cartesian
or radial coordinate systems. Relations between pressure head,
moisture content, and relative hydraulic conductivity may be
represented by functions developed by van Genuchten, Brooks and
Corey, Haverkamp and others, or by data points. Initial hydraulic
condition can be specified as static equilibrium, specified pressure
head, or specified moisture content. Boundary conditions include
specified pressure or total head, specified flux, infiltration with
ponding, evaporation, plant transpiration, and seepage faces.
Solute transport processes include advection, dispersion, first-
order decay, adsorption, and ion exchange. VS2DH is a version of
VS2DT that has been modified to simulate energy transport instead of
solute transport. Both VS2DT and VS2DH are written in Fortran 90.
Although these models are integrated into the graphical software
package, their source codes are maintained as individual Fortran
programs that can be compiled and run separately from the graphical
user interface.

[Summary provided by the USGS.]

Related URL
Description: Download VS2D.

Description: VS2D user guide.
Service Citation
Originators: Hsieh, P.A., Wingle, William, and Healy, R.W.
Title: VS2DI - A graphical software package for simulating fluid flow and solute or energy transport in variably saturated porous media
Release_Date: 2000
Provider: U.S. Geological Survey
Edition: 1.2
Access Constraints
VS2DI Version 1.2 is currently available for computers running Microsoft XP, 2000, 98, NT4.0 operating systems
Use Constraints
Support is provided for correcting bugs and clarification of how the code is intended to work. Only limited assistance can be provided for applying this software to specific problems.
Service Provider
Branch of Regional Research, Central Region, Geology Division, U.S. Geological Survey, U.S. Department of the Interior

Service Provider Personnel
Email: simcfarl at
Contact Address:
U.S. Geological Survey
Box 25046 Denver Fed. Ctr.
City: Denver
Province or State: CO
Postal Code: 80225
Country: USA
Distribution Media
Distribution_Media: Online
Distribution_Size: 20.4 MB
Fees: No fees
Contact Address:
Woods Hole Oceanographic Institute
Marine Chemistry & Geochemistry
MS 25
City: Woods Hole
Province or State: MA
Postal Code: 02543
Country: USA

Phone: (301) 614-6898
Fax: 301-614-5268
Email: Tyler.B.Stevens at
Contact Address:
NASA Goddard Space Flight Center
Global Change Master Directory
City: Greenbelt
Province or State: MD
Postal Code: 20771
Country: USA
Creation and Review Dates
SERF Creation Date: 2012-01-17
SERF Last Revision Date: 2012-01-17
[ Update this Record ]
USA dot gov - The U.S. Government's Official Web Portal NASA
Webmaster:  Monica Holland
Responsible NASA Official:  Lola Olsen
Last Updated:  December 2014