1. Numerical method for calculating heat, mass, chemical and electric fluxes through a saturated porous medium comprising: obtaining three-dimensional images of porous solid samples of said saturated porous medium; digital processing and morphological analysis of said 3D images; obtaining digital 3D models of the samples and performing a set of morphological and geometrical statistical property analysis; modeling, separately or in combination, heat, chemical and electric fluxes or combination of at least one of the heat, chemical and electric fluxes with mass fluxes for said 3D models under given boundary conditions, said modeling is made by means of a numerical solver, which is based on statistical many-body problem approach and which takes into account a functional expression for an entropy or for a Helmholtz energy, generating new models, statistically equivalent to said 3D models of the sample by means of random field and stochastic geometry theory and simulating heat, mass, chemical and electric fluxes for said new models.