A closed-form equation for predicting the hydraulic conductivity of unsaturated soils

  title={A closed-form equation for predicting the hydraulic conductivity of unsaturated soils},
  author={Van Genuchten and M. Th.},
  journal={Soil Science Society of America Journal},
  • Van GenuchtenM. Th.
  • Published 1 September 1980
  • Environmental Science
  • Soil Science Society of America Journal
A new and relatively simple equation for the soil-water content-pressure head curve, 8(h), is described in this paper. The particular form of the equation enables one to derive closedform analytical expressions for the relative hydraulic conductivity, Kr, when substituted in the predictive conductivity models of N.T. Burdine or Y. Mualem. The resulting expressions for Kr(h) contain three independent parameters which may be obtained by fitting the proposed soil-water retention model to… 

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