Liquids with a non-Newtonian rheological behavior are frequently encountered in engineering applications, where multiple phases can be involved. A rather scarcely investigated non-Newtonian behavior is thixotropy, in which the fluid’s viscosity depends on the shear rate as well as on the deformation history. In this study, a fundamental case of an oscillating droplet consisting of an ideal thixotropic fluid is numerically investigated with the in-house multiphase flow solver Free Surface 3D.
The ideal thixotropic behavior is modeled by an additional kinetic equation which involves a structural breakdown and recovery term. The influence of both terms on the evolution of the spatially averaged structural parameter λ is studied. The numerical
results show that λ oscillates around a steady-state value, which is reached quicker for faster recovery of the structure. The occurring maxima of λ are shifted in relation to the oscillation modes. This effect is more pronounced for a lower breakdown
strength and for a slower recovery rate.
%0 Conference Paper
%1 ibach2023thixotropic
%A Ibach, Matthias
%A Steigerwald, Jonas
%A Weigand, Bernhard
%D 2023
%K exc2075 myown pn1 pn1-2b updated weigand
%T Thixotropic effects in oscillating droplets
%X Liquids with a non-Newtonian rheological behavior are frequently encountered in engineering applications, where multiple phases can be involved. A rather scarcely investigated non-Newtonian behavior is thixotropy, in which the fluid’s viscosity depends on the shear rate as well as on the deformation history. In this study, a fundamental case of an oscillating droplet consisting of an ideal thixotropic fluid is numerically investigated with the in-house multiphase flow solver Free Surface 3D.
The ideal thixotropic behavior is modeled by an additional kinetic equation which involves a structural breakdown and recovery term. The influence of both terms on the evolution of the spatially averaged structural parameter λ is studied. The numerical
results show that λ oscillates around a steady-state value, which is reached quicker for faster recovery of the structure. The occurring maxima of λ are shifted in relation to the oscillation modes. This effect is more pronounced for a lower breakdown
strength and for a slower recovery rate.
@inproceedings{ibach2023thixotropic,
abstract = {Liquids with a non-Newtonian rheological behavior are frequently encountered in engineering applications, where multiple phases can be involved. A rather scarcely investigated non-Newtonian behavior is thixotropy, in which the fluid’s viscosity depends on the shear rate as well as on the deformation history. In this study, a fundamental case of an oscillating droplet consisting of an ideal thixotropic fluid is numerically investigated with the in-house multiphase flow solver Free Surface 3D.
The ideal thixotropic behavior is modeled by an additional kinetic equation which involves a structural breakdown and recovery term. The influence of both terms on the evolution of the spatially averaged structural parameter λ is studied. The numerical
results show that λ oscillates around a steady-state value, which is reached quicker for faster recovery of the structure. The occurring maxima of λ are shifted in relation to the oscillation modes. This effect is more pronounced for a lower breakdown
strength and for a slower recovery rate.},
added-at = {2023-02-06T16:02:14.000+0100},
author = {Ibach, Matthias and Steigerwald, Jonas and Weigand, Bernhard},
biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2817882bdc0ee70bfe72bc3bd146f70be/matthiasibach},
eventtitle = {11th International Conference on Multiphase Flow (ICMF), April 2–7, 2023},
interhash = {bad88c7ed2d971686aba26904f81a09e},
intrahash = {817882bdc0ee70bfe72bc3bd146f70be},
keywords = {exc2075 myown pn1 pn1-2b updated weigand},
timestamp = {2023-10-04T11:18:07.000+0200},
title = {Thixotropic effects in oscillating droplets},
venue = {Kobe, Japan},
year = 2023
}
