A grid generating algorithm for simulating a ̄uctuating water table boundary in heterogeneous uncon®ned aquifers
نویسندگان
چکیده
An algorithm is presented for generating ®nite element grids that can be used to calculate the position of a ̄uctuating water table and the formation of seepage faces within a heterogeneous uncon®ned aquifer. Our approach overcomes limitations with existing techniques by allowing the water table to rise or decline through hydrostratigraphic boundaries yet maintains numerical and conceptual accuracy with respect to hydrostratigraphic geometry. The algorithm involves (1) limited stretching or shrinking of elements along the water table if the change in the position of the water table is small with respect to the vertical grid spacing, and (2) the addition or removal of nodes and elements in the ®nite element mesh along the water table as the change becomes large with respect to the vertical grid spacing. This technique is applicable to any 2-D or 3-D ®nite element code that contains an automatic ®nite-element grid generator. Ó 1999 Elsevier Science Limited. All rights reserved
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