Lattice Boltzmann Simulation of capillary pressure curves in a rock sample

Two-phase flow of water-oil and oil-gas through a porous medium is simulated by the multi-component Boltzmann Method to determine capillary pressure curves in a heterogeneous three-dimensional pore network obtained from microphotography images of a reservoir rock. The accuracy of the model is validated by simulations of equilibrium contact angle and dynamic capillary intrusion. The simulation results show good agreement with the analytical calculation of dynamic capillary intrusion. Experimentally obtained capillary pressure curves of a hydrocarbon reservoir from the literature are consistent with our simulated capillary pressure curves. The effect of density ratio between the fluids and contact angle on the shape of the capillary pressure curve is investigated. Hysteresis is observed in all studied cases, becoming more apparent with large density differences. The density ratio is found to influence the pressure required to remove fluids from porous media and the volume of residual fluids trapped in it. The results are useful for the study of the capillary pressure curves of a reservoir and confirm that the multicomponent Lattice Boltzmann method can quantitatively determine the capillary Felipe F. Munarin Departamento de Integração Academica e Tecnológica, Universidade Federal do Ceará, Campus do Pici, 60.455-900, Fortaleza, Ceará, Brazil E-mail: munarin@fisica.ufc.br José S. Andrade Jr. Departamento de F́ısica, Universidade Federal do Ceará, Campus do Pici, 60455-760 Fortaleza, Ceará, Brazil E-mail: soares@fisica.ufc.br Francisco Nepomuceno Filho Departamento de F́ısica, Universidade Federal do Ceará, Campus do Pici, 60455-760 Fortaleza, Ceará, Brazil E-mail: nepomuceno@fisica.ufc.br Hans J. Herrmann Departamento de F́ısica, Universidade Federal do Ceará, Campus do Pici, 60455-760 Fortaleza, Ceará, Brazil E-mail: hans@fisica.ufc.br Hans J. Herrmann PMMH, ESPCI, 7 quai St. Bernard, 75005 Paris, France 2 Felipe F. Munarin et al. pressure curve for oil-water and oil-gas flow in a realistic three-dimensional rock sample.