MICROSCOPIC MECHANISMS AND INFLUENCE FACTORS OF IMMISCIBLE FLUID DISPLACEMENT IN POROUS MEDIA

In the process of water flooding there exist various mechanisms of immiscible fluid displacement at microscope pore level. In this paper we will summarize and discuss such mechanisms as pistion?like displacement, Haines' jump, creeping, snap?off, large pores trapped by small pores, fingering and by ?passing, sticking, partial film spreading and coalescence in detail. The occurrence and importance of these mechanisms depend on the external conditions (such as injection rate and injection pressure), pore geometry and structure, fluid properties, reservoir characteristics as well as interfacial tension between two different fluids. The factors affecting various displacement mechanisms are analyzed briefly on the basis of related literatures and our experiment results from slice core dynamic modeling of two fluid phases displacement.