A PSEUDO STEADY-STATE SOLUTION OF WATER MOVEMENT IN THE UNSATURATED ZONE OF THE SOIL

The vertical flow of moisture in the unsaturated zone of the soil is approached by a sequence of steady-state solutions of the flow equation. This technique allows an efficient simulation of the flow process over long periods, but restricts its application to permeable soils showing a relatively high groundwater table and to periods with either evaporation excess or rainfall excess. The pseudo steady-state solution of flow in the unsaturated zone has been incorporated a 3-dimensional mathematical model in order to solve field-size composite groundwater soil-moisture systems. Results have shown that the method is fast and sufficiently accurate, except for periods during which evaporation excess is followed by rainfall excess. A modification is suggested for bridging over periods during which evaporation excess changes into rainfall excess. The pseudo steady-state approach can also be used when the lower-boundary condition exists for a given depth of the groundwater table instead of the flux.

  • Corporate Authors:

    Elsevier Science

    Radarweg 29, P.O. Box 211
    1043NX AE Amsterdam,   Netherlands 
  • Authors:
    • De Laat, PJM
  • Publication Date: 1976-5

Media Info

  • Features: Figures; References;
  • Pagination: p. 19-27
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00158177
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Sep 28 1977 12:00AM