Skip to Main content Skip to Navigation
New interface
Theses

Écoulements de fluides à seuil en milieux confinés

Abstract : To better understand the specifics of the flow of yield stress fluids in confined geometries, we opted for a multi-scale experimental and / or numerical approach in complex and model porous media. We show the usefulness of NMR for the study of yield stress fluid's flows in complex geometry. In a porous medium, we can also measure the true probability density function of fluid velocities without spatial resolution problem thanks to a complete optimisation of the design process of a NMR-PGSE experiment. Using these measurement technics, we find that the flow of a yield stress fluid in a model pore (an axisymetric expansion-contraction) is localised in the central part of the pore, i.e. in the continuity of the entry duct, and the external region stay at rest in the solid regime. Numerical simulations confirm those results and point out that the flow localisation is due to the confinement caused by the geometry. On the contrary, no region at rest exists for a yield stress fluid flowing through a real porous media (in 3D). Furthermore, the velocity distribution is the same as a newtonian fluid. The analysis of the results makes it possible to deduce the form of the Darcy's law for yield stress fluids and provides an insight in the physical origin of the coefficients found by "macroscopical" injection experiments
Complete list of metadata

https://tel.archives-ouvertes.fr/tel-00903850
Contributor : ABES STAR :  Contact
Submitted on : Monday, February 10, 2014 - 9:43:08 AM
Last modification on : Tuesday, December 8, 2020 - 10:20:28 AM
Long-term archiving on: : Sunday, May 11, 2014 - 12:45:20 AM

File

TH2013PEST1104_complete.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-00903850, version 2

Collections

Citation

Thibaud Chevalier. Écoulements de fluides à seuil en milieux confinés. Mécanique des fluides [physics.class-ph]. Université Paris-Est, 2013. Français. ⟨NNT : 2013PEST1104⟩. ⟨tel-00903850v2⟩

Share

Metrics

Record views

578

Files downloads

2412