Mechanism of enhanced oil recovery of ultra-dry CO2-in-water foams in porous media: Experiments and numerical simulation

•The constitutive equation of CO2 foam was determined by flow experiments using tubes with different diameters.•Effects of different displacement methods on the enhanced oil recovery (EOR) were compared using the core displacement experiments.•The two-dimensional (2D) pore geometry model was constructed using the digital core method.•Effects of foam rheological properties on the displacement process were exhibited.