Enhancement of velocity contrasts by shear thinning solutions flowing in a rough fracture.

HAROLD AURADOU; ALEJANDRO BOSCHAN; RICARDO CHERTCOFF; SUSANA GABBANELLI; JEAN-PIERRE HULIN; IRENE IPPOLITO

JOURNAL OF NON-NEWTONIAN FLUID MECHANICS

Elsevier

Lugar: Amsterdam; Año: 2007

0377-0257

NOTA ACLARATORIA: Esta publicación fue aceptada (28 nov), adjunto abajo la Carta de Aceptacion (Decision Letter) del Editor.Las pruebas de galera tienen fecha para 24 diciembre 2007. RESUMEN:   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 towards a shear thinning behaviour at higher shear rates. 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 shear rates for different polymer concentrations are well predicted by ananalytical 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.CARTA DE ACEPTACION DEL EDITOR: Ms. Ref. No.:  JNNFM-D-07-00029R2Title: Enhancement of velocity contrasts by shear thinning solutions flowing in a rough fracture.Dear jean-pierre hulin,I am pleased to confirm that your manuscript, entitled "Enhancement of velocity contrasts by shear thinning solutions flowing in a rough fracture.", has been accepted for publication in the Journal of Non-Newtonian Fluid Mechanics.Elsevier production will transfer your files electronically from EES and then be in touch by email regarding proofs and copyright transferWith thanks once again for supporting JNNFM.Gareth H. McKinleyEditorJournal of Non-Newtonian Fluid Mechanicsgareth@mit.edu