Premium
Influence of Capillarity on Relative Permeability in Fractional Flows
Author(s) -
Zou Shuangmei,
Liu Yang,
Cai Jianchao,
Armstrong Ryan T.
Publication year - 2020
Publication title -
water resources research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.863
H-Index - 217
eISSN - 1944-7973
pISSN - 0043-1397
DOI - 10.1029/2020wr027624
Subject(s) - capillary pressure , capillary action , relative permeability , pressure gradient , multiphase flow , mechanics , materials science , permeability (electromagnetism) , flow (mathematics) , two phase flow , porous medium , chemistry , porosity , physics , composite material , biochemistry , membrane
The effect of capillary pressure on multiphase flow is described by the capillary pressure gradient term in the fractional flow equation. This term is typically neglected during core‐flooding experiments, as it is not easily accessible. However, the capillary pressure is not constant during core flooding owing to a capillary pressure discontinuity at the core outlet. By imaging spatial fluid distributions under two‐phase steady‐state flow, we determine in situ phase saturations and capillary pressures from interfacial curvature measurements along an entire core, thus achieving the assessment of the capillary pressure gradient and its influence on multiphase flow. We demonstrate how the pore‐scale capillary pressure gradient affects multiphase flow and, in turn, the core‐scale relative permeability measurements. Further, an alternative approach to determining relative permeability from a single fractional flow experiment is proposed. The approach provides a range of relative permeabilities for a single fractional flow experiment and does not require capillary‐end correction, as the formulation directly accounts for the effect of capillary pressure on the flow.