压力对CO2泡沫性能及岩心流动影响OA

Since the influences of pressure on the performance and seepage characteristics of CO2 foam are unclear,in this work,the effects of pressure on the foaming capability,stability,bubble diameter,plugging capacity,and oil displacement efficiency of CO2 foam were systematically investigated through experimental methods.The results showed that,the higher the pressure,the higher the foaming capacity of the CO2 foam system,however in contrast,there was a competitive mechanism in the effect of pressure on foam stability.The nano-SiO2-reinforced foam system effectively addressed the problem of instability in traditional foams.Negative correlation was observed between pressure and bubble diameter,with high-pressure conditions producing smaller and more uniform bubbles.Elevated pressure could promote the formation of CO2 foam with good uniformity and stable migration in cores.Moreover,the increased pressure could enhance the effective viscosity and plugging efficiency of CO2 foam,expanding its applicability to reservoirs with diverse ranges of permeability.High-pressure conditions could improve the oil displacement efficiency of CO2 foam flooding,alleviating the disadvantages situation caused by reservoir heterogeneity and achieving substantial oil recovery enhancement.This research might deepen the understanding of the role of pressure in CO2 foam-enhanced oil recovery and provide theoretical basis for effective gas channeling control strategies.