Influence of Steam/Water Relative Permeability Models on Predicted Geothermal Reservoir Performance: A Sensitivity Study

Abstract

The concept of relative permeabilities represents an attempt to extend Darcy's Law for single-phase flows through porous media to the two-phase flow regime. In this regime, the flowrate of each phase is related to the macroscopic pressure gradient imposed on the flow through the relative permeability parameters kL ( for the liquid phase) and kG ( for the "gas" or vapor phase), expressed as fractions of the bulk permeability (k) of the medium to all - liquid flow. Accurate "models" for kL and kG as functions of some independent flow variable ( historically liquid saturation ) are required if one is to solve the complex two-phase flow problems associated with geothermal energy extraction, nuclear waste isolation, enhanced oil recovery and others.