| Autor: |
Yu, Fang Xin, Singh, Vijay P., Yu, Fang Xin, Singh, Vijay P. |
| Zdroj: |
Journal of Irrigation and Drainage Engineering; September 1994, Vol. 120 Issue: 5 p892-909, 18p |
| Abstrakt: |
In this study, a number of theoretical improvements were made to the finiteelement formulation for modeling threedimensional steady and unsteady groundwater flow. First, the Galerkin method was combined with the collocation method to handle the timederivative term of the governing equation. Second, the resulting system of ordinary differential equations was solved by using finite integration. The principal directions of the anisotropy are not required to parallel the userselected global coordinate directions. Also, more detailed treatments to leaky boundaries, surface flux boundaries, nonhomogeneous and anisotropic aquifers, and sources/sinks are presented. The improved formulation was coded in FORTRAN. Four example cases were used to verify the model. It was found that the model is stable, accurate, and numerically oscillation free if proper timestep size is used. A critical review of the commonly used finitedifference solution scheme is given. A detailed discussion of how to obtain accurate numerical solutions while avoiding numerical oscillation is presented. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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