Pore network modelling of low salinity water injection under unsteady-state flow conditions

The study shows that the impact of LS injection can often be difficult to predict a priori for any given combination of rock/fluid parameters and laboratory protocol, due to the complex way in which the underlying parameters interact. When compared against high salinity (HS) data, both positive and negative LS effects have been observed depending upon the prevailing system properties and the timing of LS initiation. However, by running a series of network modelling simulations, we are able to identify areas of parameter space that are more likely to elicit a positive LS response. In particular, we observe that a change in the dominant flow regime (capillary fingering, viscous fingering, frontal advance) may be induced by the injection of LS brine and this has been found to play an important role in determining LS efficacy.