HR: 1340h
AN: H33F-0533    [Abstracts]
TI: Optimal Mesh Generation for AEM-based Eulerian Transport Simulators
AU: * Craig, J R
EM: jrcraig2@acsu.buffalo.edu
AF: Department of Civil, Structural, and Environmental Engineering, University at Buffalo, 207 Jarvis Hall, Buffalo, NY 14260-4400 United States
AU: Rabideau, A J
EM: rabideau@eng.buffalo.edu
AF: Department of Civil, Structural, and Environmental Engineering, University at Buffalo, 207 Jarvis Hall, Buffalo, NY 14260-4400 United States
AU: Matott, L S
EM: lsmatott@acsu.buffalo.edu
AF: Department of Civil, Structural, and Environmental Engineering, University at Buffalo, 207 Jarvis Hall, Buffalo, NY 14260-4400 United States
AB: The analytic element method (AEM) is a grid-independent approach for simulating groundwater flow in shallow aquifer systems. Recent advances have enabled AEM flow solutions to be used as the basis for Eulerian (finite difference or finite element) contaminant transport simulators. One of the benefits of such a merger is the removal of the constraints imposed by the flow grid or mesh. The resultant model discretization may be specified to accommodate only the relevant transport constraints (i.e., the Peclet and Courant limitations). Design of the mesh is typically limited by discretization requirements of the flow problem. With the use of AEM flow solutions, grid and mesh geometry may be optimized for a specific transport system without regard for flow system discretization. A two-dimensional mesh generation algorithm is presented that maximizes the required node spacing (governed by Peclet limitations) and therefore the time step (governed by Courant limitations) required for transport models using the spatially continuous velocities and dispersion coefficients obtained from AEM flow solutions. The optimized meshes reduce the computational cost of contaminant transport models by reducing the total number of degrees of freedom. Results from the optimized mesh algorithm illuminate some artifacts of flow discretization that are commonly neglected. The increased computational efficiency of models simulated without these discretization artifacts is quantified, and some non-intuitive results concerning the optimal mesh design for transport simulation are presented.
UR: http://www.groundwater.buffalo.edu
DE: 1832 Groundwater transport
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting