10월 25일(목)․지하수학
2007 추계지질과학연합학술대회 초록집
213Kirchhoff Transformation Approach for Simulating Steady-State Variably Saturated Groundwater Flow
Ji, Sung-Hoon1,*
․Park, Young-Jin
2․Sudicky, Edward A.
2․Sykes, Jon F.
31KAERI, HLW Disposal Research Center, [email protected]
2University of Waterloo, Department of Earth and Environmental Sciences
3University of Waterloo, Department of Civil and Environmental Engineering
A numerical method is proposedto accurately and efficiently compute a direct steady-state solution for the nonlinear Richards’equation. In the proposed method, the Kirchhoff integral transformation and a complimentary transformation are applied to the governing equation in order to separate the nonlinear hyperbolic characteristic from the linear parabolic. The separation allows the transformed governing equation to be applied to partially- to fully-satu- rated systems with arbitrary constitutive relationsbetween primary (pressure head) and sec- ondary variables (relative permeability). The transformed governing equation is then dis- cretized to solve withcontrol volume finite difference/finite element approximations, followed by an inverse transformation. The proposed approach is compared to analytical and other numerical approaches for variably-saturated flow in 1- and 3-D domains. The results clearly demonstrate that the proposed approach is not only more computationally efficient but also more accurate. The approach is also applied to a regional groundwater flow in a variably satu- rated heterogeneous system, where the vadose zone is up to 1 km thick. The stability and effectiveness of the proposed approach is manifested for a complex heterogeneous irregular system.
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