COMPOSITIONAL SIMULATION OF GROUNDWATER CONTAMINATION BY ORGANIC-COMPOUNDS .1. MODEL DEVELOPMENT AND VERIFICATION

A compositional simulator is developed for application to the analysis of contamination and remediation of groundwater systems. Simultaneous flow of three fluid phases (water, gas, and organic) is modeled. Inte rphase partitioning and transport of an arbitrary number of organic an d inorganic components can be simulated. Phase densities are functions of pressure and phase composition. The model includes several numeric al options, ranging from fully implicit with first-order upstream weig hting to implicit in pressure, explicit in saturations and concentrati on with third-order upstream weighting. The model is verified to the e xtent possible with analytical solutions for simplified cases of multi phase flow and contaminant transport. The accuracy and efficiency of t he various numerical options used in the model are illustrated.