IWNET12
IWNET12
Steady-state, simultaneous two-phase ow in porous media: An exper-
imental study
Knut Måløy1
1 University in Oslo, Norway
Abstract
We report on experimental studies of steady-state two-phase ow in a quasi-two-dimensional porous medium.
The wetting and the nonwetting phases are injected simultaneously from alternating inlet points into a Hele-
Shaw cell containing one layer of randomly distributed glass beads, initially saturated with wetting uid. The
high viscous wetting phase and the low viscous nonwetting phase give a low viscosity ratio M = 10−4. Transient
behavior of this system is observed in time and space. However, we nd that at a certain distance behind the
initial front a "local" steady-state develops, sharing the same properties as the later "global" steady state. In
this state the nonwetting phase is fragmented into clusters, whose size distribution is shown to obey a scaling
law, and the cuto cluster size is found to be inversely proportional to the capillary number. The steady state
is dominated by bubble dynamics, and we measure a power-law relationship between the pressure gradient
and the capillary number. In fact, we demonstrate that there is a characteristic length scale in the system,
depending on the capillary number through the pressure gradient that controls the steady-state dynamics. We
have further studied the reversibility of the steady state by changing the injection rate and then returning back
to the original injection rate.
E-mail: k.j.maloy@fys.uio.no

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