Shear-induced fractures and three-dimensional motions in an organogel

Pauline Grondin (1) , Sébastien Manneville (2) , Jean-Luc Pozzo (3) , Annie Colin (4)

1 CRPP - Centre de recherches Paul Pascal
2 Phys-ENS - Laboratoire de Physique de l'ENS Lyon
3 LCOO - Laboratoire de chimie organique et organométallique
4 LOF - Laboratoire du Futur

The flow behavior of a viscoelastic organogel is investigated using ultrasonic velocimetry combined with rheometry. Our gel presents a decreasing flow curve, i.e., the measured stress decreases as a function of the applied shear rate. Strikingly, we note that the local flow curve calculated from the velocity profiles also exhibits a decreasing part. We attribute this regime to the presence of a fracturing process and three-dimensional motions in the bulk of the sample.

Mots clés: Physical gels and microgels; Material behavior; Non-Newtonian fluid flows; Acoustical measurements and instrumentation

Domaines: Matière Molle [cond-mat.soft]

Pauline Grondin, Sébastien Manneville, Jean-Luc Pozzo, Annie Colin. Shear-induced fractures and three-dimensional motions in an organogel. Physical Review E : Statistical, Nonlinear, and Soft Matter Physics, 2008, 77 (1), pp.11401. ⟨10.1103/PhysRevE.77.011401⟩. ⟨ensl-00526126⟩