1. General Model Information



Main medium: terrestrial
Main subject: hydrology
Organization level: Ecosystem
Type of model: partial differential equations (finite elements,3D)
Main application:
Keywords: unsaturated, water flow, solute transport, porous medium, non-porous medium,fractures, fracture network


D.D. Evans

University of Arizona
Tucson, AZ 85721


Rasmussen, T.C., and D.D. Evans


The BIM/FRACGEN package simulates flow and (advective) solute transport in unsaturated, fractured, porous or non-porous media. It solves the boundary value problem within intersecting fracture planes using the boundary integral method applied to two- (BIM2D) and three-dimensional (BIM3D) formulations for flow using a constant capillary head within individual fractures. The transport problem is solved through calculating travel times and breakthrough curves by integrating the inverse velocity over a streamline, and then summing over all streamlines. The transport equation includes linear equilibrium reversible sorption (retardation) and diffusion from fractures into the rock matrix and v.v. FRACGEN generates synthetic fracture networks for sensitivity analysis with respect to fracture network parameters. The program BIM provides estimates of steady flow rates, hydraulic head distributions, travel times and breakthrough curves for discrete fracture networks, incorporating both saturated and variably saturated flow. The program BIM2D is used to dicretize the fracture network and then solve for steady fluid flow and transport using the boundary integral method. It is limited to applications involving non-porous rock. The program BIM3D is used to study coupled flow through a fracture network embedded within a permeable matrix. The program FRACGEN is used to determine the global hydraulic conductivity of a fractured rock mass by generating finite fractures within a specified rock volume and then solving the finite lines of intersections between fractures and between fractures and the rock volume boundary. It uses site-specific geometric data, or generates synthetic fractures.

Source of the Abstract:CSMoS online

II. Technical Information

II.1 Executables:

Operating System(s): DOS, public domain

II.2 Source-code:

Programming Language(s): FORTRAN, public domain

II.3 Manuals:

II.4 Data:

III. Mathematical Information

III.1 Mathematics

III.2 Quantities

III.2.1 Input

III.2.2 Output

IV. References

V. Further information in the World-Wide-Web

VI. Additional remarks

Last review of this document by: Wed Oct 8 10:21:20 1997
Status of the document:
last modified by Tobias Gabele Wed Aug 21 21:44:39 CEST 2002

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