Scaling spontaneous imbibition of water data accounting for fluid viscosities

Spontaneous imbibition (SI) of water into the matrix blocks is regarded as a very important driving mechanism for oil recovery in dual porosity media. Oil recovery from such reservoirs is usually determined by mass transfer function between matrix and fracture. A new dimensionless scaling group has been developed which is able to correctly account for variation in fluid viscosities (imbibing fluid viscosity larger than initial fluid viscosity) when scaling spontaneous imbibition data generated by numerical simulation. The new dimensionless time is clearly superior to the usual scaling group established by Ma et al. (1997) when correlating the spontaneous imbibition data.