A study on mixed electro-osmotic/pressure-driven microchannel flows of a generalised Phan-Thien-Tanner fluid

• Type: Article in International Scientific Journal
• Date: 2021

Authors

Ângela M. Ribau (Author) Other; Luís L. Ferrás (Author) Other; Maria Luísa Morgado (Author) Other; Magda Rebelo (Author) Other; Manuel Alves (Author) Other; Fernando T. Pinho (Author) FEUP; Alexandre M. Afonso (Author) FEUP

Journal

Title: Journal of Engineering Mathematics

Vol. 127

Pages: 1-15

ISSN: 0022-0833

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 10 Citations

Scopus - 10 Citations

Associated Projects

MOLDPRO - Aproximações multi-escala para moldação por injeção de materiais plásticos

Other information

Authenticus ID: P-00T-JMB

DOI: 10.1007/s10665-020-10071-6

Abstract (EN): This work presents new semi-analytical solutions for the combined fully developed electro-osmotic pressure-driven flow in microchannels of viscoelastic fluids, described by the generalised Phan-Thien-Tanner model (gPTT) recently proposed by Ferras et al. (Journal of Non-Newtonian Fluid Mechanics, 269:88-99, 2019). This generalised version of the PTT model presents a new function for the trace of the stress tensor-the Mittag-Leffler function-where one or two new fitting constants are considered in order to obtain additional fitting flexibility. The semi-analytical solution is obtained under sufficiently weak electric potential that allows the Debye-Huckel approximation for the electrokinetic fields and for thin electric double layers. Based on the solution, the effects of the various relevant dimensionless numbers are assessed and discussed, such as the influence of epsilon Wi(2), of the parameters alpha and beta of the gPTT model, and also of (kappa) over bar, the dimensionless Debye-Huckel parameter. We conclude that the new model characteristics enhance the effects of both epsilon Wi(2) and (kappa) over bar. on the velocity distribution across the microchannels. The effects of a high zeta potential and of the finite size of ions are also studied numerically.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 15