Pore-Scale Network Models for Multi-Phase Flow and Contaminant Transport in Porous Media
Saturday, January 15, 2000 - 11:30am - 12:30pm
Pore-scale network models for two-phase flow in porous media provide explicit information about all fluid-fluid interfaces within a porous medium, for any set of imposed pressure conditions. Because the interfaces are tracked explicitly as they move through the network, all quantities associated with the interfaces can be calculated, including non-traditional variables like interfacial areas and contact line lengths. These variables are important in certain new mathematical theories for multi-phase flow, and they are also important to more immediately practical problems such as dissolution of non-aqueous phases across fluid-fluid interfaces and subsequent miscible transport of those contaminants in the aqueous phase. In this presentation, I will outline the underlying ideas inherent in pore-scale network models, demonstrate that they are capable of reproducing measured quantities and traditional multi-phase constitutive relationships, use them to investigate new conjectures regarding behavior of interfacial areas and common line lengths, and present computational results involving non-aqueous-phase dissolution and subsequent miscible transport. The dissolution results will be used to investigate the problem of upscaling effective mass transfer coefficients for use in continuum-scale transport equations. Limitations of the model will be discussed, and future developments to overcome these limitations will be outlined.