Search results
Results from the WOW.Com Content Network
A classical torsion wire-based du Noüy ring tensiometer. The arrow on the left points to the ring itself. The most common correction factors include Zuidema–Waters correction factors (for liquids with low interfacial tension), Huh–Mason correction factors (which cover a wider range than Zuidema–Waters), and Harkins–Jordan correction factors (more precise than Huh–Mason, while still ...
Surface tension is the tendency of liquid surfaces at rest to shrink into the minimum surface area possible. Surface tension is what allows objects with a higher density than water such as razor blades and insects (e.g. water striders) to float on a water surface without becoming even partly submerged.
The spinning drop method is convenient compared to other widely used methods for obtaining interfacial tension, because contact angle measurement is not required. Another advantage of the spinning drop method is that it is not necessary to estimate the curvature at the interface, which entails complexities associated with shape of the fluid drop.
Interfacial and surface tension can be characterized by classical methods such as the -pendant or spinning drop method. Dynamic surface tensions, i.e. surface tension as a function of time, can be obtained by the maximum bubble pressure apparatus. The structure of surfactant layers can be studied by ellipsometry or X-ray reflectivity.
in which is the number of core samples, is the effective porosity, is the absolute permeability, is the interfacial tension or IFT, and is the imbibition or secondary drainage capillary pressure data vs. normalized water saturation.
The magnitude of the capillary force on the plate is proportional to the wetted perimeter, = +, and to the surface tension of the liquid-air interface. A Wilhelmy plate is a thin plate that is used to measure equilibrium surface or interfacial tension at an air–liquid or liquid–liquid interface.
where is the dynamic viscosity of the liquid, is a characteristic velocity and is the surface tension or interfacial tension between the two fluid phases. Being a dimensionless quantity, the capillary number's value does not depend on the system of units.
Surfactants can have a significant effect on the spreading coefficient. When a surfactant is added, its amphiphilic properties cause it to be more energetically favorable to migrate to the surface, decreasing the interfacial tension and thus increasing the spreading coefficient (i.e. making S more positive).