The development of intermittent multiphase fluid flow pathways through a porous rock

摘要: Abstract Intermittent fluid flow has recently been identified as an important transport mode for processes involving subsurface multiphase fluids such CO 2 storage and natural gas production. However, due to experimental limitations, it not possible identify why intermittency occurs at conditions what the implications are upscaled properties relative permeability. We address these questions with observations of nitrogen brine flowing steady-state through a carbonate rock. overcome previous imaging limitations high-speed (1s resolution), synchrotron-based X-ray micro-computed tomography combined pressure measurements recorded while controlling flux. observe that intermittent allows non-wetting phase more ramified network pores, which would be connected pathway alone same rate. The volume intermittently fluctuating increases capillary number, corresponding expansion minimising role inertial forces in even rate increases. sits energetically between laminar turbulent pathways. While favours lowered permeability, is dissipative than pathways, permeability remains unchanged low numbers where pore geometry controls location intermittency. number further, structure decreases corresponds increase These can serve basis model causal links flow, distribution throughout space, manifestation