Unsteady 1D flow in unconfined nonuniform aquifers

Onder H., Banna S.

International Water Resources Engineering Conference on Water Resources Development and Protection, Tennessee, United States Of America, 3 - 07 August 1998, pp.51-56 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • City: Tennessee
  • Country: United States Of America
  • Page Numbers: pp.51-56
  • Middle East Technical University Affiliated: No


A one-dimensional groundwater now occurring in a finite, unconfined, nonuniform aquifer, which consists in two different regions, is considered. The aquifer is limited on one side by a flood channel and by an impervious formation on the other side. The flow occurs as a result of a sudden drop (or a rise) in the water stage of the flood channel. The now is investigated by two approaches; experimentally in a sandbox model in the laboratory and numerically using a digital model based on finite differences. The results are presented in the form of dimensionless graphs that represent the variation of the dimensionless drawdowns in the first and second regions of the aquifer, and the dimensionless bank storage as a function of dimensionless time. The results of experimental investigation are in a reasonable agreement with those of the numerical investigation. except for early time. The deviation at early time is due to the fact that Dupuit assumptions are not satisfied. The results of the present work are also compared with those of the analytical results. This comparison shows also a good agreement, except at early time where the Dupuit assumptions are not satisfied.