Calculation of Advective Mass Transport in Heterogeneous Media
Abstract
A coupled analytical/numerical procedure for prediction of solute transport in heterogeneous media is described. The procedure consists of an analytic solution of the hydraulic equations, followed by a numerical solution for solute transport using the method of characteristics. The characteristics are determined by fourth-order Runge-Kutta and predictor-corrector algorithms. Accuracy of solute transport calculation is enhanced by the fact that fluid velocity can be directly obtained at a priori undetermined points in the flow field. The solute transport process is considered to be entirely advective, neglecting the effects of mechanical dispersion and molecular diffusion. Evidence is presented to demonstrate that purely advective processes in both heterogeneous and homogeneous media can produce large apparent dispersion. Such dispersion is shown to be easily capable of overwhelming any reasonable estimates of dispersion of diffusion based upon laboratory analyses of homogeneous media. For groundwater contamination problems, it is concluded that precise definition of the spatial variability of hydraulic properties is crucial to the accurate determination of the trajectory of contaminated waters.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1983
- Accession Number
- ADP001015
Entities
People
- Charles J. Daly
Organizations
- Cold Regions Research and Engineering Laboratory