Rhéologie des mousses de fluides complexes

Abstract : The subject of this experimental thesis is the study of the rheology of complex fluid foams. The use of model materials allows decoupling the effects of the bubbles and the complex fluid on the rheological behavior of the foams. In particular, we characterize the elastic modulus and the yield stress of particle-loaded foams and emulsion foams. The rheology of particle-loaded foams is highly dependent on the size ratio between the particle and the interstitial foam network (node and the so called “Plateau borders”). When the particles are small enough to be included in the foam network, they can form a compact granular skeleton. This structure put in place by the drainage of the suspension substantially increases the value of the elastic modulus of the particle-loaded foams. Indeed, the confinement exerted by the bubbles on the granular skeleton is at the origin of the elasticity of the matrix (skeleton). As the size of the particles increases, they are excluded from the foam network and the elastic modulus of the foam particles decreases with the disappearance of the matrix. Particle foams with a granular skeleton have the advantage of having two distinct sources of elasticity: the capillary elasticity of the bubbles and the elasticity of the granular skeleton. These two contributions can be summed up to model the macroscopic elastic modulus of the foam, this is not the case for emulsion foams. Indeed, there is a coupling between bubbles and the emulsion matrix. The introduction of elastic capillary number and the Bingham number allows to describe the respective evolution of the elastic modulus and the yield stress of the emulsion foams. Finally, the analysis of the yield stress of these two types of foams enables to identify the matrix of particles as a yield stress fluid, and forms an interesting parallel between these two foams that are a priori dissimilar
Keywords : Rheology Foam Suspension
Complete list of metadatas

https://pastel.archives-ouvertes.fr/tel-01743684
Contributor : Abes Star <>
Submitted on : Monday, March 26, 2018 - 4:13:08 PM
Last modification on : Thursday, May 16, 2019 - 1:46:06 PM
Long-term archiving on : Thursday, September 13, 2018 - 10:53:03 AM

File

TH2017PESC1227.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-01743684, version 1

Collections

Citation

François Gorlier. Rhéologie des mousses de fluides complexes. Science des matériaux [cond-mat.mtrl-sci]. Université Paris-Est, 2017. Français. ⟨NNT : 2017PESC1227⟩. ⟨tel-01743684⟩

Share

Metrics

Record views

322

Files downloads

395