Research associate, Manchester Centre for Nonlinear Dynamics (MCND)
School of Physics and Astronomy
I am currently working under the joint supervision of Anne Juel and Andrew Hazel on the invasion by an air finger of an initially fluid-filled channel. In the context of airway reopening, this project investigates the propagation of the air finger in partially occluded, elasto-rigid channels. Thanks to an experimental set-up consisting of a rigid channel of variable depth in cross section, topped with a thin elastic membrane, we aim at decoupling the effect of channel geometry and wall elasticity on the propagation modes of the air finger.
I completed my PhD in September 2014 on the rheological behaviour of foamed yield stress fluids. This work was conducted in Laboratoire Navier (Université Paris-Est, Champs-sur-Marne, France), under the supervision of Guillaume Ovarlez (now at LOF, Pessac, France), Olivier Pitois (page under construction, I'm afraid) and Julie Goyon (page in French). This project was led in collaboration with Saint-Gobain Recherche (Aubervilliers, France), as part of a wider research effort to design innovative building materials. In this experimental work, we dispersed monodisperse bubbles in simple yield stress fluids (concentrated oil in water emulsions), and measured the rheology of the resulting aerated yield stress fluids. For low to moderate volume fractions, the small deformation elastic modulus, the yield stress and the consistancy are all governed by the coupling of the suspending fluid's rheology to capillarity acting on the bubbles. Quantitative agreement is found with micro-mechanical estimates developped by Xavier Chateau (Laboratoire Navier) to take this coupling into account. High gas volume fractions remain widely unexplored, as our first experimental observations have evidenced a very different arrangement of oil droplets and gas bubbles in what becomes a foam from yield stress fluid. If you are curious (and can read French!), you can find my thesis here.
I worked for a short research project (Master's internship) with Nick Hayman (Institute for Geophysics, University of Texas at Austin, USA) and Karen Daniels (North Carolina State University, USA) on the mechanics of sheared 2D granular materials. We aimed at better understanding the behaviour of granular fault gouge during earthquakes. Model experiments were performed by shearing a layer of photoelastic disks, with a view to linking grain scale behaviour (grain displacement and force chain evolution) to the macroscopic behaviour of the analog "fault" (boundary displacement and applied shear force).