1. General Model Information

Name: FUSSIM2 1.0 - Flow in Unsaturated Soil SImulation Model in 2 dimensions (Heinen and De Willigen, 1992).

Acronym: FUSSIM2

Main medium: terrestrial
Main subject: hydrology
Organization level: Cropping system/animal husbandry system.
Type of model: partial differential equations (finite elements,2D)
Main application:
Keywords: soil, unsaturated, flow, water transport, richards equation, finite elements


Ir. M. Heinen.
Research Institute for Agrobiology and Soil Fertility (AB-DLO), , P.O.Box 129, 9750 AC Haren (Gr.), THE NETHERLANDS.
Phone: +31.50.5337353
Fax: +31.50.5337291
email: m.heinen@ab.dlo.nl



Solves the non-linear Richards' equation in 2 dimensions (x,z). Soil hydraulic properties described by Van Genuchten-Mualem functions. Richards' equation is left in mixed 0-h form. Method proposed by Celia et al. (1990; WRR 26: 1483-96) is used to assure perfect mass balance. Solution is obtained numerically using the control volume finite element method. The resulting matrix problem is solved via an iterative alternating direction implicit method. Top and bottom boundary conditions can be of prescribed pressure head or prescribed flux density type; left and right boundaries are no flow boundaries.

Purpose of the model:

Model parentage: -

Source of the AbstractCAMASE Register of Agro-ecosystems Models

II. Technical Information

II.1 Executables:

Operating System(s): IBM compatible, VAX, ALPHA. Contract necessary: Costs: : Dfl. 110,=.

II.2 Source-code:

Programming Language(s): Microsoft FORTRAN-77.

II.3 Manuals:

II.4 Data:

III. Mathematical Information

III.1 Mathematics

III.2 Quantities

Rate variables: Flux density in x and z, actual sink term (transpiration), rain/irrigation, actual soil evaporation.

State variables: Pressure head h, volumetric water content 0, differential moisture capacity C, hydraulic conductivity K, total water storage, total change in water storage, van Genuchten-Mualem parameters: Os, Or, alpha, n, Ks, labda.

III.2.1 Input

Number of columns and layers, thickness of columns and layers, van Genuchten-Mualem parameters: Os, Or, alpha, n, Ks, labda, type of top boundary condition, rain/irrigation per time unit, actual soil avaporation, sink term distribution, type of and values of bottom boundary condition, initial h distribution, initial time step, maximum time step, maximum allowable change in 0 per time step, print interval, stop time, iterations convergence criterion, maximum allowable iterations, desired output data. Input check in model: No.

III.2.2 Output

Summary of input data, grid point locations, time, total water storage, total change since start, error in mass balance, 0 per node, h per node, K per node, C per node, total head H per node, Fx and Fz at control volume boundaries.
Basic spatial unit: cm.
Time interval of simulation: Constant or variable; unit depending on units of input data.

IV. References

Heinen, M. & P. de Willigen, 1992. FUSSIM2: a simulation model for two-dimensional flow of water in unsaturated soil. DLO-Instituut voor Bodemvruchtbaarheid Nota 260. 146 pp.

V. Further information in the World-Wide-Web

VI. Additional remarks

Parentage: -
Last review of this document by: T. Gabele: Tue Sep 24 1997
Status of the document:
last modified by Joachim Benz Mon Jul 2 18:31:37 CEST 2007

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