HR: 1340h
AN: H23E-1474    [Abstracts]
TI: Efficient Algorithm for Modeling Mass Transport in Porous Media with Mass Exchange between Mobile Fluid and Stationary Medium
AU: * Mendoza-Sanchez, I
EM: itzam@neo.tamu.edu
AF: Instituto Politécnico Nacional, Escuela Superior de Ingeniería y Arquitectura, Unidad Zacatenco, Cd. de México, 07700 Mexico
AU: Cunningham, J A
EM: cunning@eng.usf.edu
AF: University of South Florida, Department of Civil & Environmental Engineering, Tampa, FL 33620 United States
AB: We compare two approaches to numerically solve the mathematical model of reactive mass transport in porous media with mass exchange between mobile fluid and stationary medium. The first approach, named the ``traditional method,'' solves a single system of differential equations that results from a standard finite-difference discretization of the governing equations. The second approach, named the ``direction-splitting method,'' solves two separate systems of differential equations: one for transport in the mobile fluid, and one for uptake and reaction in the stationary medium. The two systems are coupled by a boundary condition at the mobile-immobile interface, and are solved iteratively. The direction-splitting method is appealing because it involves the solution of two smaller systems compared to that of the traditional method; thus the computation time may be greatly reduced if the iterative method converges rapidly. Also, the direction-splitting method employs a modular code that can easily be modified to accommodate different mathematical representations of the physical phenomena (e.g., different models for biodegradation kinetics within the stationary medium). Each module of the code can employ a different numerical algorithm to optimize the solution. The main objectives of the present study are: (1) to quantitatively compare the two approaches in terms of computation time, and (2) to determine the conditions under which the direction-splitting method is superior to the traditional method.
DE: 1832 Groundwater transport
SC: Hydrology [H]
MN: Fall Meeting 2005