Quoted from: https://www.usgs.gov/software/vs2di-version-13 

The VS2DI package contains all the tools that a user needs to create, run, and view results for a simulation of flow and transport through variably saturated porous media. The package seamlessly integrates a graphical user interface--within which the user can draw the simulated domain and enter or modify model parameters--with existing USGS models of flow and solute transport, and a postprocessor that displays simulation results.

The VS2DI software package includes three applications:

1. VS2DTI for simulation of water and solute transport
2. VS2DHI for simulation of water and energy transport
3. VS2POST, a standalone postprocessor for viewing results saved from previous simulation runs

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). These models have been updated to version 3.3 for implementation in the VS2DI package.

Summary of VS2DI

New in Version 1.3

• Compatibility with Windows7 and Vista (32 and 64 bit).
• Gravity drain boundary condition - allows gravity driven vertical fow out of the domain assuming a unit vertical hydraulic gradient but does not allow flow into the domain.
• Rossi-Nimmo hydraulic functions - Rossi, C., and Nimmo, J.R., 1994, Modeling of soil water retention from saturation to oven dryness. Water Resourse Research, v. 30, no. 3, p. 701-708.
• Revised output formats.

Experienced users of VS2DT and VS2DH will find that it is now much easier to construct simulations and to analyze results.

Users unfamiliar with VS2DT and VS2DH will find that the VS2DI package allows for easy and rapid examination of water and contaminant (or heat) movement through various different hydrologic regimes. It is an excellent tool for hypothesis testing (for example, for looking at the influence that the shape, position, and hydraulic characteristics of a layer of low permeability have on the movement of a contaminant infiltrating from the soil surface). VS2DI is also very useful for teaching the basics of soil physics and subsurface contaminant transport. Typical applications of the programs are for studies of ground-water recharge, surface-water-ground-water exchange, and contaminant transport from waste disposal sites. An extensive on-line help manual provides all the information necessary to run the programs.

Download Current Version of VS2DI

VS2DI Version 1.3 is currently available for computers running Microsoft Windows operating systems. Example problems and tutorials for both VS2DT and VS2DH are contained in a zip file. The examples are designed to help the user learn the software and to allow testing of the software after installation. Windows executable files for VS2DT and VS2DH are included in the VS2DI Version 1.3 download. Users may also download the fortran source code directly.

• VS2DI Version 1.3 compiled for Microsoft Windows (39 MB)
• VS2DI Examples and Tutorials (4.5MB)
• Windows Installation Instructions
• VS2DT Version 3.3 fortran source code (0.2MB)
• VS2DH Version 3.3 fortran source code (0.2MB)

Some users may wish to run the numerical models VS2DT and VS2DH independently from the graphical user interface. Instructions for running these models separately (from a DOS command prompt window) are given in Batch Instructions. Instructions for modifying the ascii input files vs2dt.dat and vs2dh.dat are given in vs2dt3_3InputInstructions.pdf and vs2dh3_3InputInstructions.pdf.

Documentation for VS2DI

The software package includes on-line help manuals that provide detailed information on how to set up and run a simulation. To access the on-line help manual, run the software and select "Contents" form the "Help" menu. In addition, the following reports are available:

Hsieh, P.A., Wingle, William, and Healy, R.W., 2000, VS2DI--A graphical software package for simulating fluid flow and solute or energy transport in variably saturated porous media: U.S. Geological Survey Water-Resources Investigations Report 99-4130, 16 p. USGS WRIR 99-4130, Portable Document Format (PDF) (116K)

Healy, R.W., and Ronan, A.D., 1996, Documentation of computer program VS2DH for simulation of energy transport in variably saturated porous media -- modification of the U.S. Geological Survey's computer program VS2DT: U.S. Geological Survey Water-Resources Investigations Report 96-4230, 36 p. An electronic version of this report can be downloaded from:http://pubs.er.usgs.gov/pubs/wri/wri964230

Healy, R.W., 1990, Simulation of solute transport in variably saturated porous media with supplemental information on modifications to the U.S. Geological Survey's Computer Program VS2D: U.S. Geological Survey Water-Resources Investigations Report 90-4025, 125 p. An electronic version of the report can be downloaded from:http://pubs.er.usgs.gov/pubs/wri/wri904025

Lappala, E.G., Healy, R.W., and Weeks, E.P., 1987, Documentation of computer program VS2D to solve the equations of fluid flow in variably saturated porous media: U.S. Geological Survey Water-Resources Investigations Report 83-4099, 184 p. An electronic version of the report can be downloaded from: http://pubs.er.usgs.gov/pubs/wri/wri834099.

Software License and Purchase Information

This software is a product of the U.S. Geological Survey, which is part of the U.S. Government.

Cost

This software is freely distributed. There is no fee to download and (or) use this software.

License

Users do not need a license or permission from the USGS to use this software. Users can download and install as many copies of the software as they need.

Public Domain

As a work of the United States Government, this USGS product is in the public domain within the United States. You can copy, modify, distribute, and perform the work, even for commercial purposes, all without asking permission. Additionally, USGS waives copyright and related rights in the work worldwide through CC0 1.0 Universal Public Domain Dedication (https://creativecommons.org/publicdomain/zero/1.0/ ).

SOFTWARE USER RIGHTS NOTICE

This software has been approved for release by the U.S. Geological Survey (USGS). Although the software has been subjected to rigorous review, the USGS reserves the right to update the software as needed pursuant to further analysis and review. No warranty, expressed or implied, is made by the USGS or the U.S. Government as to the functionality of the software and related material nor shall the fact of release constitute any such warranty. Furthermore, the software is released on condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from its authorized or unauthorized use. Also refer to the USGS Water Resources Software User Rights Notice for complete use, copyright, and distribution information.

Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.