Purely-elastic flow instabilities and elastic turbulence in microfluidic cross-slot devices

• Type: Article in International Scientific Journal
• Date: 2018

Authors

Sousa, PC (Author) FEUP; F. T. Pinho (Author) FEUP; Alves, MA (Author) FEUP

Journal

Title: Soft Matter

Vol. 14

Pages: 1344-1354

ISSN: 1744-683X

Publisher: Royal Society of Chemistry

Indexing

ISI Web of Knowledge - 4 Citations

Scopus - 24 Citations

Other information

Authenticus ID: P-00N-P8G

DOI: 10.1039/c7sm01106g

Abstract (EN): We experimentally investigate the dynamics of viscoelastic fluid flows in cross-slot microgeometries under creeping flow conditions. We focus on the unsteady flow regime observed at high Weissenberg numbers (Wi) with the purpose of understanding the underlying flow signature of elastic turbulence. The effects of the device aspect ratio and fluid rheology on the unsteady flow state are investigated. Visualization of the flow patterns and time-resolved micro-particle image velocimetry were carried out to study the fluid flow behavior for a wide range of Weissenberg numbers. A periodic flow behavior is observed at low Weissenberg numbers followed by a more complex dynamics as Wi increases, eventually leading to the onset of elastic turbulence for very high Weissenberg numbers.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 11