# Solvent Ideal Gas Law¶

Defines the solvent as an ideal gas. See example with ideal density and enthalpy:

EOS SOLVENT
DENSITY IDEAL
ENTHALPY IDEAL_CO2
VISCOSITY CONSTANT 0.03 cP
END


The type of ideal gas for the computation of enthalpy purposes can take the following values: IDEAL_METHANE, IDEAL_CO2. This value cannot be defaulted, for thermal problems or the code will return an error.

Viscosity units are optional, if not entered will default to $$Pa.s$$

The density is modelled with gas ideal law:

$\rho( P , T )= \frac{P}{RT},$

where:

$R = 8.31446,$

the gas ideal constant, units sJ/(mol K).

The Enthalpy will be computed differently based on the type of ideal gas selected above.

For IDEAL_METHANE the Enthalpy will be computed as:

$h(T )= p_T,$

where:

$c_p = 35.69,$

the constant pressure heat capacity of methane, units J/(mol K), at T = 288.15 K, P=1 bar.

For IDEAL_CO2 the Enthalpy will be computed as:

$h(T )=c_v T + RT,$

where:

$c_v = 28.075,$

the constant volume heat capacity of CO2, units J/(mol K), at T = 15 C and P= 1 atm.