EOS#

TOUGH3 currently includes all equation-of-state (EOS) modules of the Version 2 of TOUGH2, as well as ECO2N (Pan et al., 2015, Pruess, 2005), ECO2M (Pruess, 2011), EOS7C (Oldenburg et al., 2004), EOS7CA (Oldenburg, 2015), and TMVOC (Pruess & Battistelli, 2002).

Table 66 Fluid property modules for TOUGH3.#
Module	Capabilities
EOS1	water, water with tracer
EOS2	water, CO₂
EOS3	water, air
EOS4	water, air, with vapor pressure lowering
EOS5	water, hydrogen
EOS7	water, brine, air
EOS7R	water, brine, air, parent-daughter radionuclides
EOS7C	water, brine, CO₂ (or N₂), gas tracer, CH₄
EOS7CA	water, brine, non-condensible gas, gas tracer, air
EOS8	water, “dead” oil, non-condensible gas
EOS9	variably-saturated isothermal flow according to Richard’s equation
EWASG	water, salt (NaCl), non-condensible gas
TMVOC	water, water-soluble volatile organic chemicals, non-condensible gases, with biodegradation
ECO2N	water, NaCl, CO₂
ECO2M	water, NaCl, CO₂, including transitions between super- and sub-critical conditions, and phase change between liquid gaseous CO₂