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Numerical simulation of an unsaturated flow equation


A numerical model for an unsaturated flow problem by using the finite element method is established in order to simulate liquid moisture flow In an unsaturated zone with homogeneous soil and deep subsurface water, and with different initial and boundary conditions. For infiltration or evaporation problems, a traditional method usually yields oscillatory non-physics profiles. However, nonoscillatory solutions are obtained and non-physics solutions for these problems are evaded by using the mass-lumped finite element method. Moreover, the kind of boundary condition is handled very well.

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Author information

Correspondence to Zhenghui Xie or Qingcun Zeng or Yongjiu Dai or Bin Wang.

Additional information

Project supported by the National Key Project of Fundamental Research ”Climate Dynamics and Climate Prediction Theory“ and China Postdoctoral Science Foundation.

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Xie, Z., Zeng, Q., Dai, Y. et al. Numerical simulation of an unsaturated flow equation. Sci. China Ser. D-Earth Sci. 41, 429–436 (1998).

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  • unsaturated flow
  • finite element
  • mass lumping
  • numerical simulation