English

Self-sustaining oscillations of a falling sphere through Johnson-Segalman fluids

Mathematical Physics 2012-09-11 v2 math.MP Numerical Analysis

Abstract

We confirm numerically that the Johnson-Segalman model is able to reproduce the continual oscillations of the falling sphere observed in some viscoelastic models. The empirical choice of parameters used in the Johnson-Segalman model is from the ones that show the non-monotone stress-strain relation of the steady shear flows of the model. The carefully chosen parameters yield continual, self-sustaining, (ir)regular and periodic oscillations of the speed for the falling sphere through the Johnson-Segalman fluids. In particular, our simulations reproduce the phenomena: the falling sphere settles slower and slower until a certain point at which the sphere suddenly accelerates and this pattern is repeated continually.

Keywords

Cite

@article{arxiv.1209.1328,
  title  = {Self-sustaining oscillations of a falling sphere through Johnson-Segalman fluids},
  author = {Young-Ju Lee and Chen-Song Zhang},
  journal= {arXiv preprint arXiv:1209.1328},
  year   = {2012}
}