Stabilizing effect of shear thinning on the onset of purely elastic instabilities in serpentine microflows

• Type: Article in International Scientific Journal
• Date: 2016

Authors

Laura Casanellas (Author) Other; Manuel A. Alves (Author) FEUP; Robert J. Poole (Author) Other; Sandra Lerouge (Author) Other; Anke Lindner (Author) Other

Journal

Title: Soft Matter

Vol. 12 No. 29

Pages: 6167-6175

ISSN: 1744-683X

Publisher: Royal Society of Chemistry

Indexing

ISI Web of Knowledge - 11 Citations

ISI Web of Science

Scopus - 24 Citations

Other information

Authenticus ID: P-00K-PFP

DOI: 10.1039/C6SM00326E

Abstract (EN): We determine both experimentally and numerically the onset of elastic flow instabilities in viscoelastic polymer solutions with different levels of shear thinning. Previous experiments realized in microfluidic serpentine channels using dilute polymeric solutions showed that the onset of elastic instabilities strongly depends on the channel curvature. The scaling dependence is well captured by the general instability scaling criterion proposed by Pakdel and McKinley [Phys. Rev. Lett., 1996, 76, 2459: 1-4]. We determine here the influence of fluid shear thinning on the onset of such purely-elastic flow instabilities. By testing a set of polyethylene oxide solutions of high molecular weight at different polymer concentrations in microfluidic serpentine channels we observe that shear thinning has a stabilizing effect on the microfluidic flow. Three-dimensional numerical simulations performed using the White-Metzner model predict similar trends, which are not captured by a simple scaling analysis using the Pakdel-McKinley criterion.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9