Solitary Vortex Pairs in Viscoelastic Couette Flow
Abstract
We report experimental observation of a localized structure, which is of a new type for dissipative systems. It appears as a solitary vortex pair (``diwhirl'') in Couette flow with highly elastic polymer solutions. In contrast to the usual solitons the diwhirls are stationary. It is also a new object in fluid dynamics-a pair of vortices that build a single entity. The diwhirls arise as a result of a purely elastic instability through a hysteretic transition at negligible Reynolds numbers. It is suggested that the vortex flow is driven by the same forces that cause the Weissenberg effect.
- Publication:
-
Physical Review Letters
- Pub Date:
- February 1997
- DOI:
- 10.1103/PhysRevLett.78.1460
- arXiv:
- arXiv:patt-sol/9610008
- Bibcode:
- 1997PhRvL..78.1460G
- Keywords:
-
- Nonlinear Sciences - Pattern Formation and Solitons
- E-Print:
- 9 pages (LaTeX), 5 Postscript figures, submitted