Solution of water-table and anisotropic flow problems by using the strongly implicit procedure

S. P. Larson; Peter C. Trescott

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USGS · 70233523

Solution of water-table and anisotropic flow problems by using the strongly implicit procedure

S. P. Larson·Peter C. Trescott

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Abstract

The use of the strongly implicit procedure (SIP) with an additional iteration parameter, β , to scale the residual vector is advantageous to the solution of some ground-waterflow problems. For steady-state water-table problems plagued by excessive elimination of grid blocks during the iteration process, selection of β <1 can be effective in limiting the deletion of blocks to a reasonable number. Also, a linear problem characterized by large anisotropy and layers of contrasting hydraulic conductivity was solved more efficiently with β =1.5. Effective values of β are generally in the range 0< β <2 and are easily determined by trial. Use of a β parameter in the SIP algorithm provides an effective solution technique for a class of ground-water-flow problems that previously was burdened by significant computational difficulty.

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S. P. Larson, Peter C. Trescott. 1977. Solution of water-table and anisotropic flow problems by using the strongly implicit procedure. https://pubs.usgs.gov/publication/70233523

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