Effect of advancing velocity and fluid viscosity on the dynamic contact angle of petroleum hydrocarbons

The goal of this research was to study the effect of advancing velocity and liquid viscosity on the dynamic contact angle between a solid surface and various hydrocarbons. The Wilhelmy plate technique was used to measure the dynamic contact angle at advancing velocities between 20 and 264 μm/s. In addition to hydrocarbons, two silicon oils were also tested for comparison purposes. The results indicate that advancing velocity and oil viscosity have a significant effect on the dynamic contact angle for both hydrocarbon and silicon oils. For example, the advancing contact angle for viscous (1540 mPa s at 15 °C) oils was up to 2 times higher at 200 μm/s than at 20 μm/s. As a result, it is recommended that when values for dynamic contact angles are reported, the advancing velocity at which they were measured be indicated. This will ensure correct data interpretation, meaningful comparison between various studies, and better prediction of multiphase flow or adhesion processes that depend on the dynamic contact angle. © 2007 Elsevier B.V. All rights reserved.