The kernel-conformation constitutive laws

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

Authors

A. M. Afonso (Author) FEUP; F. T. Pinho (Author) FEUP; M. A. Alves (Author) FEUP

Journal

Title: Journal of Non-Newtonian Fluid Mechanics

Vol. 167 No. JAN 2012

Pages: 30-37

ISSN: 0377-0257

Publisher: Elsevier

Indexing

ISI Proceedings

ISI Web of Knowledge - 17 Citations

ISI Web of Science

Scopus - 28 Citations

INSPEC

Scientific classification

FOS: Engineering and technology > Mechanical engineering

Associated Projects

ELECTROELASTIC - ELECTROELASTIC – Escoamento por electro-osmose de fluídos viscoelásticos em microgeometrias

MICROMIXING - Sistemas passivos de mistura em microgeometrias para escoamentos de fluidos viscoelásticos

Other information

Authenticus ID: P-002-H3X

DOI: 10.1016/j.jnnfm.2011.09.008

Abstract (EN): This work presents a generic kernel-conformation tensor transformation for a large class of differential constitutive models, in which several matrix kernel-transformation families can be applied to the conformation tensor evolution equation. The discretization of this generic analytical framework generates numerical results consistent with the standard conformation tensor discretization at low Weissenberg numbers (Wi). The numerical efficiency of High Weissenberg Number Problems is ultimately related with both the specific kernel function used in the matrix transformation, but is also related to the existence of mathematical singularities introduced either by the physical description of the flow or by the characteristics of the adopted constitutive equation. We also show that the log-conformation [R. Fattal, R. Kupferman, J. Non-Newtonian Fluid Mech., 123(2-3) (2004) 281-285] and the square-root-conformation [N. Balci, B. Thomases, M. Renardy, C.R. Doering, J. Non-Newtonian Fluid Mech., 166(11) (2011) 546-553] approaches are two relevant particular cases of the kernel-conformation tensor transformation. Simulations for the benchmark confined cylinder flow of an Oldroyd-B fluid provide a preliminary assessment of the merits of some tested transformation functions.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8