Lucie Ducloué

Coupling of elasticity to capillarity in soft aerated materials

We study the elastic properties of soft solids containing air bubbles. Contrary to standard porous materials, the softness of the matrix allows for a coupling of the matrix elasticity to surface tension forces acting on the bubble surface. Thanks to appropriate experiments on model systems, we demonstrate how the elastic response of the soft porous solid is governed by two dimensionless parameters: the gas volume fraction and a capillary number comparing the elasticity of the matrix with the stiffness of the bubbles. Furthermore, we show that our experimental results are accurately predicted by computations of the shear modulus through a micro-mechanical approach.

Mixtures of foam and paste: suspensions of bubbles in yield stress fluids

We study the rheological behavior of mixtures of foams and pastes, which can be described as suspensions of bubbles in yield stress fluids. Model systems are designed by mixing monodisperse aqueous foams and concentrated emulsions. The elastic modulus of the bubble suspensions is found to depend on the elastic capillary number

Granular Controls on Periodicity of Stick-Slip Events: Kinematics and Force-Chains in an Experimental Fault

\textit{Ca}_{_G}

Rheological behaviour of suspensions of bubbles in yield stress fluids

, defined as the ratio of the paste elastic modulus to the bubble capillary pressure. For values of

Reopening modes of a collapsed elasto-rigid channel

\textit{Ca}_{_G}

Viscous fingering and dendritic growth under an elastic membrane

larger than

Yielding and flow of foamed metakaolin pastes

\simeq 0.5

Rheological properties of suspensions of bubbles in a yield stress fluid

, the dimensionless elastic modulus of the aerated material decreases as the bubble volume fraction

Rheological properties of bubble suspensions in yield stress fluids

\phi

Rheological properties of Bubble suspensions in yield stress fluids

increases, suggesting that bubbles behave as soft elastic inclusions. Consistently, this decrease is all the sharper as