Experiment Study On CO₂ Foam Fluid Reological Characteristics In Tubes

CO₂ foam flooding as an important technology for EOR has great potential to enhanced oil recovery and carbon dioxide geological storage. For understanding foam fluid behavior in porous media, experimental investigations were carried out concerning lamellae foam rheological characteristics in tubes. Foam is treated as a two-phase fluid, and the governing non-dimensional parameters were obtained through theoretical analysis, the rheological characteristics of the foam lamellae were analyzed and given the resistance model based on two-phase flow.It is clearly observed that a startup pressure is necessarily needed for mobilizing the foam lamellae in tubes（circular tubes or converging-diverging tubes）, and therefore indicate the Herschel-Bulkley model instead of the power-law model could be better in revealing the mechanism of flowing foams in porous media in large scale.N2 foam lamellae needs a greater startup pressure compared with CO₂ foam lamellae to start flowing in the tube. Comparisons among experimentally obtained mechanistic models and present popular models reveal a similar trend however much higher pressure value in the selected rate range of the experiment. Foam film lamellae flowing in a converging-diverging tube which needs to overcome a greater startup pressure compared with flowing in a straight circular tube.In this paper, in order to better simulate reservoir environment, the paper designs a complete set of experimental devices that can be test high temperature and high pressure CO₂ foam fluid rheological characteristics or supercritical carbon dioxide foam fluid rheological characteristics. The key technology of the device is that it can accurately observe the foam flow patterns in the tube and make a precise measurement of its resistance characteristics. In the date analysis, the flow patterns and rheologicalcharacteristics of supercritical（high temperature and high pressure） CO₂ foam fluid can be studied together.