Berlin 2024 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
DY: Fachverband Dynamik und Statistische Physik
DY 45: Wetting, Fluidics and Liquids at Interfaces and Surfaces (joint session CPP/DY)
DY 45.2: Talk
Thursday, March 21, 2024, 15:15–15:30, H 0107
How rheology influences the wetting behavior of droplets — •Günter K. Auernhammer1, Peyman Rostami1, Reza Azizmalayeri1, Valentine Comoy1, and Mathis Fricke2 — 1Leibniz Institute of Polymer Research Dresden, Germany — 2Department of Mathematics, TU Darmstadt, Germany
We study the spreading of viscous and viscoelastic drops on solid substrates with different wettability. In the early stages of spreading, we find that the viscoelastic drop spreads with faster and a different power law than the Newtonian drop (i.e. aqueous glycerine solution) for the same zero shear rate viscosity. We argue that the effect of viscoelasticity is only observable for experimental time scales in the order of the internal relaxation time of the polymer solution or longer times. Near the contact line, the effective viscosity is lower for the viscoelastic drop than for the Newtonian drop. Together with its shear rate dependency, this difference in effective viscosity can explain the different spreading dynamics. We support our experimental findings with a simple perturbation model that qualitatively agrees with our findings. [https://arxiv.org/abs/2308.14515]
Keywords: Dynamic Wetting; Non-Newtonian rheology; Relaxation time