HR: 1340h
AN: H23G-1713    [Abstracts]
TI: Simulation of transport under random retardation using CTRW: Impact of small scale spatial heterogeneity on effective transport.
AU: * Castro-Ledesma, A D
EM: adolfo.castro@upc.edu
AF: Dept. of Geotechnical Engineering and Geosciences -Technical University of Catalonia (UPC), Jordi Girona 1-3; Building D2, Barcelona, BCN 08034, Spain
AU: Dentz, M
EM: marco.dentz@gmail.com
AF: Dept. of Geotechnical Engineering and Geosciences -Technical University of Catalonia (UPC), Jordi Girona 1-3; Building D2, Barcelona, BCN 08034, Spain
AU: Sanchez-Vila, X
EM: xavier.sanchez-vila@upc.edu
AF: Dept. of Geotechnical Engineering and Geosciences -Technical University of Catalonia (UPC), Jordi Girona 1-3; Building D2, Barcelona, BCN 08034, Spain
AB: We study the impact of small scale spatial heterogeneity on effective transport. Small scale heterogeneity is represented explicitly by a spatial random retardation factor that is fluctuating on a length scale much smaller than the observation scale. Using continuous time random walks (CTRW) as a coarse graining tool, the heterogeneity distribution can be mapped directly on the distribution of transition times. The latter renders an explicit effective transport model that is completely defined by the small scale heterogeneity distribution. We conduct a series of random walk simulations in order to validate the theoretical findings. Numerical experiments in d=1, 2 and 3 spatial dimensions study spatial and temporal aspects of solute transport in terms of spatial distributions as well as solute breakthrough curves. These findings are used for the interpretation of actual field transport measurements. The experimental findings are in agreement with theoretical predictions.
DE: 1832 Groundwater transport
DE: 1839 Hydrologic scaling
DE: 1849 Numerical approximations and analysis
DE: 1869 Stochastic hydrology
SC: Hydrology [H]
MN: 2007 Fall Meeting