INTERFACIAL EFFECTS UPON THE DISPLACEMENT AND STATIC STABILITY OF INTERFACES IN CAPILLARY SYSTEMS WITH SPECIAL APPLICATION TO TERTIARY OIL RECOVERY

The effect of the interfacial viscosities upon two-phase displacement in capillary systems is quantitatively determined. The conditions leading to static stability of interfaces in sinusoidal pore are also presented.;In Chapter III the effect of the interfacial viscosities upon the pressure and flow fields generated by the displacement of a gas by a liquid in the channel formed between two parallel plates is determined. The contact angle is assumed to be 90(DEGREES). Under restricted conditions the excess pressure drop due to the interfacial viscosities can be calculated independent of any parameters arising in the model used to describe slip in the neighborhood of the common line.;In Chapter IV a thermodynamic analysis is used to predict the stable, static positions of a liquid-liquid interface in a sinusoidal pore as a function of pressure drop. Contact angle hysteresis effects are taken fully into account. Results show that instabilities can lead to spontaneous adjustment of the contact angle as well as spontaneous movement of the common line. An extension of the analysis to two interfaces shows the cooperative effect that one interface has on the stability of another.;In Chapter I an integral mechanical energy balance is used to explain the relative effects of the interfacial viscosities, interfacial tension, and wetting during displacement in a single, cylindrical capillary. For values of the contact angle greater than 0(DEGREES) and less than 180(DEGREES), the effect of the interfacial viscosities is to increase the resistance to displacement regardless of the wetting condition. The predictions of a prior qualitative theory for the relative effects of the interfacial viscosities and of interfacial tension during tertiary oil recovery are fully supported by this analysis. The result is presented in the form of a generalized Washburn equation. A similar approach is used in Chapter II to determine the relative effects of the interfacial viscosities, interfacial tension, and wetting upon displacement in a capillary whose radius is a sinusoidal function of axial position. The conclusions are consistent with Chapter I.