Titre : |
General aspects of yield stress fluids - Terminology and definition of viscosity |
Type de document : |
texte imprimé |
Auteurs : |
Martin Boisly, Auteur ; Markus Kästner, Auteur ; Jörg Brummund, Auteur ; Volker Ulbricht, Auteur |
Année de publication : |
2014 |
Article en page(s) : |
11 p. |
Note générale : |
Bibliogr. |
Langues : |
Anglais (eng) |
Catégories : |
Fluides non newtoniens Fluides, Mécanique des Rhéologie Viscosité
|
Tags : |
'Fluide de stress' 'Viscosité différentielle' Viscosité apparente' 'Contrainte d'équilibre' 'Elément friction' 'Élément Bingham' |
Index. décimale : |
532.05 Mécanique des fluides et des liquides - Dynamique (cinétique et cinématique) |
Résumé : |
This work contributes to general theoretical aspects of yield stress fluids with significance for practical phenomenological material modeling. It introduces a terminology so that the material class 'yield stress fluid' is defined and can be distinguished from the terms `solid' and liquide. This new material classification is based on two criteria, the equilibrium relation and the flow function. In line with this terminology, an experimental procedure for classifying the material behavior is presented. The second key aspect of this paper is a discussion on the proper definition of the term 'viscosity'. The benefit of the differential viscosity over the dynamic viscosity in case of non-Newtonian fluids in general is worked out. This is shown by the most ele-mentary yield stress fluid, the friction element, because it is the basis of the yield stress concept. Its constitutive equations are given for positive as well as negative strain rates and are also able to represent the preyield behavior. The theory presented in this article is also applied to the Maxwell, Kelvin-Voigt, and Bingham element to demonstrate the working principle. |
Note de contenu : |
- SPLIT OF THE TOTAL STRESS INTO AN EQUILIBRIUM AND OVERSTRESS
- DIFFERENTIAL VISCOSITY DEFINED BY THE STEADY STATE MATERIAL RESPONSE TO A CONSTANT STRAIN RATE LOADING
- CLASSIFICATION OF MATERIAL BEHAVIOR INTO THREE TYPES : SOLIDS, LIQUIDS AND YIELD STRESS FLUIDS
- DISCUSSION OF THE DIFFERENTIAL VISCOSITY AND DEMONSTRATION OF THE FUNCTIONALITY OF THE MATERIAL CLASSIFICATION BY STANDARD AND EXTENDED RHEOLOGICAL ELEMENTS : Constitutive equations of standard rheological elements used to illustrate the theoretical statements of this article - Illustrating the benefit of a differential viscosity by standard rheological elements - Application of the material classification to standard rheological elements - Application of the material classification to extended rheological elements |
Référence de l'article : |
14578 |
DOI : |
10.3933/ApplRheol-24-14578 |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=21555 |
in APPLIED RHEOLOGY > Vol. 24, N° 1 (2014) . - 11 p.