A representation of the equations of multicomponent multiphase seepage

Onset of Darcy–Bénard convection in a horizontal layer of dual-permeability medium with isothermal boundaries

“…If one of the works is neglected and the other one is taken into account, then the dissipation term is not quadratic, and the dissipation can become negative. The governing equations thus contradict the second law of thermodynamics (Afanas'ev 2012). Therefore, both works must be either taken into account or neglected.…”