Patrick M. Knupp Distinguished Member Technical Staff Applied Mathematics & Applications Dept.

Numerical Subsurface Flow and Transport

I have been involved in numerical groundwater hydrology, porous media flow, and contaminant transport, adapting existing hydrology and transport codes in environmental compliance assessments. I've managed software/algorithm development projects for radionuclide transport and am principle author of a 3D groundwater flow code that simulates a moving water-table using a free-surface boundary condition algorithm and a finite volume approach. This code was used to model regional flow in the Delaware Basin of New Mexico and the Murray Basin in Australia. I was co-principle investigator on a project "High Accuracy Robust Groundwater Flow and Transport Codes for Environmental Engineering" for Armstrong Lab, Environics Directorate, the U.S. Air Force.

Publications:

1. T. Corbet, C. Ho, P. Knupp, and J. Ramsey, "Review and Verification of the MINEDW Groundwater Flow Code," Sandia National Laboratories, December 4, 1998.
2. (with J.C. Helton, et. al.) "Uncertainty and sensitivity analysis results obtained in the 1992 performance assessment for the waste isolation pilot plant," Reliability Engineering and System Safety, 51, pp53-100, 1996.
3. "A Moving Mesh Algorithm for 3-D Regional Groundwater Flow with Water Table and Seepage Face," Advances in Water Resources, Vol. 19, No. 2, pp83-95, 1996.
4. (with J. Lage). "Generalization of Forchheimer-extended Darcy Flow Model to Tensor Permeability Case via a Variational Principle," Journal of Fluid Mechanics, vol 299, pp97-104, 1995.
5. (with K. Salari) "Contributions of an Analytic Solution to a 2D Radionuclide Transport Problem for Site Performance Assessment," in Computer Techniques for Environmental Studies IV, P. Zannetti ed., Proceedings of '92 Environsoft Conference, Computational Mechanics Pubs., Southampton UK, 1992.
6. (with K. Salari, P. Roache, and S. Steinberg) "TVD Applied to Radionuclide Transport in Fractured Porous Media." Proceedings of IX International Conference on Computational Methods in Water Resources, Vol. I, pp141-148, Denver, 1992.
7. (with P.J. Roache et al) "Experience with Benchmark Test Cases for Groundwater Flow," ASME FED Vol. 93, Benchmark Test Cases for Computational Fluid Dynamics, I. Celik and C.J. Freitas eds., 1990.