HR: 1340h
AN: H23B-1309    [Abstracts]
TI: Comparative Inverse Modeling With Combination of Multiphysics Codes and Parameter Estimation Snap-on Tools
AU: * Haeri, H
EM: hhaeri@ucdavis.edu
AF: Department of Civil and Environmental Eng., UC Davis, 1 Sheilds Ave., Davis, CA 95616, United States
AU: Foglia, L
EM: lfoglia@ucdavis.edu
AF: Department of Civil and Environmental Eng., UC Davis, 1 Sheilds Ave., Davis, CA 95616, United States
AU: Foglia, L
EM: lfoglia@ucdavis.edu
AF: Larry Walker Associates, 707 Fourth Street, Davis, CA 95616, United States
AU: Ginn, T R
EM: trginn@ucdavis.edu
AF: Department of Civil and Environmental Eng., UC Davis, 1 Sheilds Ave., Davis, CA 95616, United States
AB: Inverse problems in hydrology and hydrogeology are challenging due to non-uniqueness and/or instability yet ubiquitous in parameter estimation for distributed parameter models. One avenue to reduction of non- uniqueness involves use of multiple data sets governed by the same aquifer property to be estimated; i.e., piezometric head (supposedly governed by a diffusion equation) can be coupled with tracer or inferred age data (supposedly governed by an advection-dispersion-reaction equation). In such a case both head and concentration/age data may be used to help robustness in the inverse problem solution. In the recent years several so-called "multiphysics" simulation tools have been developed which can simultaneously solve coupled sets of PDE-based physical equations representing different processes often at distinct scales. Employing such multiphysics simulation tools lets us couple complex physical phenomena such as fluid flow in subsurface, solute fate and transport, heat transfer etc. Employing a general multiphysics computational framework for specification of the forward model can facilitate handling of multiple data types in indirect inversions to determine particular parameter values common to the coupled models. We report on a preliminary investigation into an indirect inversion of a benchmark case (due to Sudicky, 1989) of steady-state fluid flow and transient solute transport through a vertical cross section in an unconfined aquifer. Solute enters the domain through a finite section of the upper boundary, and undergoes nonuniform transport due to large scale heterogeneity in aquifer properties. We apply multiphysics modeling in the forward sense to solve simultaneously the flow and solute transport equations, the output of which is used as input to an indirect inversion scheme using UCODE_2005 (Poeter et al. 2007) to calibrate some of the parameters involved. Furthermore a multimodel analysis (Poeter and Hill, 2007) was applied to disciminate between the different models developed. We use comparative simulations to evaluate some of the aspects of the multiphysics computing framework in this context and report on the capabilities of the different tools used in this demonstration problem and their computational performances under different grid resolutions and zonation strategies.
DE: 1829 Groundwater hydrology
DE: 1832 Groundwater transport
DE: 1846 Model calibration (3333)
SC: Hydrology [H]
MN: 2007 Fall Meeting