Under dynamic conditions, the dynamic contact angle (the angle that the liquid makes with the solid) of a liquid on a solid surface varies dramatically with substrate velocity from its equilibrium value. Experimental data of the dynamic contact angles for polydimethylsiloxane (PDMS or silicone oil) under air on a glass substrate coated with teflon, for water under PDMS, for solutions of the polymer polyethylene oxide (PEO) under air, for solutions of PEO under PDMS, were obtained to simulate and understand the systems of brine or brine containing a polymer displacing viscous crude. A variety of solid substrates were used other than above to displace oil with the object that the equilibrium contact angles ~ 90⁰. The method used was that of a plate immersed or withdrawn from a pool of liquid, and the machine (Cahn-Thermo) calculates for us the dynamic advancing and receding contact angles. The dynamic contact angles determine the basic driving forces such as capillary pressures. The data were correlated with a number of available models. In most cases, the models were developed further to fit the requirements of various cases. In general, it is necessary for the model to include fluid flow, interfacial phenomena, and rheology. Photography was used to verify cases of entrainment and instability. One object of the present work was to determine the contribution of the non-Newtonian nature of the PEO solution. For the PEO solution under oil (PDMS) no obvious signs are observed although solutions at high polymer concentrations, that is, high elasticity, show some anomalous effects. However, it is not possible to conclude that shear thinning effects will be absent in all cases since a criterion is established here that shows under what condition the above may not hold --Abstract, page iv
