The Study of the Boundary Viscosity of Organic Liquids by the Blow-off Method

A method is described for the investigation of the boundary viscosity of liquids based on the fact that, when a layer of liquid flows on a flat wall under the influence of a stream of gas flowing above it, the film assumes a wedge-shaped form (the blow-off method). It is shown that the profile of the resulting wedge resembles that of the velocity profile, which makes it possible to determine from this profile the viscosity as a function of the distance to the support. Another method for the layer-by-layer determination of the viscosity is based on the measurement of the thickness of the film as a function of the duration of the blow-off process at a specific distance from the wetting boundary. In order to determine the film profile, optical and especially ellipsometric methods have been used.
In order to extend the range of objects of study, a method has been developed for the investigation of the boundary viscosity of volatile liquids and its theory has been specified. It has been applied to hexadecane and it has been observed that the viscosity decreases at short distances from the wall.
The bibliography includes 68 references.