Abstract:
The work is dedicated to the surface rheology of solutions of organic substances. On the basis of experimental data, the analysis of phase shifts between the rheological curves of surface tension and surface area of an oscillating drop has been carried out. It is shown that in low-viscosity liquids (propanol-2, distilled water and chlorophyll solution) the dilatation of the surface tension of the oscillating drop is in the frequency range from 1 to 2 Hz.The threshold frequency of hovering drop oscillation for propanol-2 at which the periodicity of nonequilibrium surface tension is demonstrated is established.The dependence of the phase shift between the sinusoidal curves of surface tension and the area of an oscillating drop on the shear rate and the concentration of organic components in solutions has been studied. The obtained nonlinear rheological properties of the systems allow to determine the viscoelastic parameters of the studied liquid.
Fulltext:
PDF file (547 kB)