User's Guide for Hysteretic Capillary Pressure and Relative Permeability Functions in iTOUGH2

摘要

The precursor of TOUGH2, TOUGH, was originally developed with non-hysteretic characteristic curves. Hysteretic capillary pressure functions were implemented in TOUGH in the late 1980s by Niemi and Bodvarsson (1988), and hysteretic capillary pressure and relative permeability functions were added to iTOUGH2 about ten years later by Finsterle et al. (1998). Recently, modifications were made to the iTOUGH2 hysteretic formulation to make it more robust and efficient (Doughty, 2007). Code development is still underway, with the ultimate goal being a hysteretic module that fits into the standard TOUGH2 (Pruess et al., 1991) framework. This document provides a user's guide for the most recent version of the hysteretic code, which runs within iTOUGH2 (Finsterle, 1999a,b,c). The current code differs only slightly from what was presented in Doughty (2007), hence that document provides the basic information on the processes being modeled and how they are conceptualized. This document focuses on a description of the user-specified parameters required to run hysteretic iTOUGH2. In the few instances where the conceptualization differs from that of Doughty (2007), the features described here are the current ones.