Abstract: Based on macrodimensional conventional fluid phase equilibrium thermodynamic theory, such interfacial physical chemistry effects as capillary pressure, surface adsorption and capillary condensation etc., are introduced. Meanwhile, stress sensitivity research of the accumulation and permeability characteristic in pore media and capillary radius are correlated by Ko ZenyCarman equation, then, the microdimensional fluidsolid coupling phase equilibrium thermodynamic mathematical model of multiphasefluidsolid coupling dew point pressure, pT phase diagram and fixed volume depletion gas condensate reservoir with low permeability and superlow permeability, which considers formation stress deformation and interfacial physical chemistry effect is establishted. The simulation result of phase behavior indicates that this model can properly explain experiment results of condensate gas and oil system in pore media.

Key words: deformable porous media, interfacial phenomena, condensate gas reservoir, gas and oil system, phase equilibrium