Table 1 List of secondary variables and their dependency on the primary variables

Gas phase saturation

S(P,X)

[-]

Molar density of phase α

N _α (P,X,T)

[mol m ⁻³]

Molar fraction of component i in phase α

\(X_{\alpha }^{(i)}(P,X,T)\)

[-]

Capillary pressure

P _c (S)

[ Pa]

Relative permeability of phase α

K _{r α} (S)

[-]

Specific internal energy of phase α

u _α (P,X,T)

[J mol ⁻¹]

Specific enthalpy of phase α

H _α (P,X,T)

[J mol ⁻¹]

Heat conduction coefficient

λ _pm (P,X,S,T)

[W m ⁻¹ K ⁻¹]