High performance microfluidic rectifiers for low inertia flow

• Type: Article in International Scientific Journal
• Date: 2012

Authors

Patrícia C. Sousa (Author) FEUP; Fernando T. Pinho (Author) FEUP; Mónica S. N. Oliveira (Author) FEUP; Manuel A. Alves (Author) FEUP

Journal

Title: RSC Advances

Vol. 2

Pages: 920-929

ISSN: 2046-2069

Publisher: Royal Society of Chemistry

Indexing

ISI Web of Science

Scientific classification

FOS: Engineering and technology

Associated Projects

OPTIMAL - Optimização de microdispositivos para escoamento de fluidos viscoelásticos

Other information

DOI: 10.1039/C1RA00803J

Abstract (EN): The flow of Newtonian and non-Newtonian fluids within microfluidic rectifiers with a hyperbolic shape was investigated to assess the effect of the bounding walls on the diodicity of the microfluidic device and achieve high flow anisotropy. Three microchannels were used, with different depths and the same geometrical configuration, which creates a strong extensional flow and generates high anisotropic flow resistance between the two flow directions. The Newtonian fluid, de-ionized water, was used as a reference fluid. The viscoelastic fluid used was an aqueous solution of polyethylene oxide (0.1% w/w) with high molecular weight. The flow patterns were visualized using streak photography and the velocity field was investigated using micro-particle image velocimetry. Moreover, pressure drop measurements were performed in order to compare the diodicity achieved in the microfluidic rectifiers. For the Newtonian fluid flow, the experimental results are compared with numerical predictions obtained using a finite-volume method and good agreement was found between both approaches. For the viscoelastic fluid, significant anisotropic flow resistance can be achieved. The effect of the bounding walls was analysed and found to be qualitatively similar for all microchannels. Nevertheless, in quantitative terms, the diodicity is enhanced when the wall effect is reduced, i.e. when the channels are deeper. A maximum diodicity above six was found for the deeper channel, a value well beyond those previously reported

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10