Velocity contrasts enhancement for shear thinning solutions flowing in a rough fracture
| Autor: | Auradou, Harold, Boschan, Alejandro, Chertcoff, Ricardo, Gabbanelli, Susana, Hulin, Jean-Pierre, Ippolito, Irene |
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| Přispěvatelé: | Grupo de Medios Porosos [Buenos Aires] (GMP), Facultad de Ingeniería [Buenos Aires] (FIUBA), Universidad de Buenos Aires [Buenos Aires] (UBA)-Universidad de Buenos Aires [Buenos Aires] (UBA), Fluides, automatique, systèmes thermiques (FAST), Université Paris-Sud - Paris 11 (UP11)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS) |
| Jazyk: | angličtina |
| Rok vydání: | 2007 |
| Předmět: |
[PHYS.PHYS.PHYS-FLU-DYN]Physics [physics]/Physics [physics]/Fluid Dynamics [physics.flu-dyn]
Condensed Matter::Soft Condensed Matter Physics::Fluid Dynamics fracture polymer Fluid Dynamics (physics.flu-dyn) FOS: Physical sciences shear thinning macro dispersion Physics - Fluid Dynamics hydrodynamic dispersion |
| Popis: | Flow and transport are studied in transparent model fractures with rough complementary self-affine walls with a relative shear displacement $\vec{u}$. The aperture field is shown to display long range correlations perpendicular to $\vec{u}$: for flow in that direction, the width and geometry of the front of a dyed shear-thinning polymer solution displacing a transparent one have been studied as a function of the fluid rheology and flow rate. The front width increases linearly with distance indicating a convection of the fluids with a low transverse mixing between the flow paths. The width also increases with the flow-rate as the fluid rheology shifts from Newtonian at low shear rates $\dot \gamma$ towards a shear thinning behaviour at higher $\dot \gamma$ values. The width also increases with the polymer concentration at high flow-rates. These results demonstrate the enhancement of the flow velocity contrasts between different flow channels for shear thinning fluids. The relative widths at low and high $\dot \gamma$ values for different polymer concentrations are well predicted by an analytical model considering the fracture as a set of parallel ducts of constant hydraulic apertures. The overall geometry of the experimental front geometry is also predicted by the theoretical model from the aperture map. |
| Databáze: | OpenAIRE |
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