Physics – Condensed Matter – Soft Condensed Matter
Scientific paper
2010-10-29
Physics
Condensed Matter
Soft Condensed Matter
6 Pages, 4 figures. To appear in Europhysics Letters
Scientific paper
A tenuous monolayer of hydrophobic particles at the air-water interface often forms a scum or raft. When such a monolayer is disturbed by the localized introduction of a surfactant droplet, a radially divergent surfactant shock front emanates from the surfactant origin and packs the particles into a jammed, compact, annular band with a packing fraction that saturates at a peak packing fraction $\phi^*$. As the resulting two-dimensional, disordered elastic band grows with time and is driven radially outwards by the surfactant, it fractures to form periodic triangular cracks with robust geometrical features. We find the number of cracks $N$ and the compaction band radius $R^*$ at fracture onset vary monotonically with the initial packing fraction ($\phi_{init}$). However, its width $W^*$ is constant for all $\phi_{init}$. A simple geometric theory that treats the compaction band as an elastic annulus, and accounts for mass conservation allows us to deduce that $N \simeq 2\pi R^*/W^* \simeq 4\pi \phi_{RCP}/\phi_{init}$, a result we verify both experimentally and numerically. We show the essential ingredients for this phenomenon are an initially low enough particulate packing fraction that allows surfactant driven advection to cause passive jamming and eventual fracture of the hydrophobic particulate interface.
Bandi Mahesh
Mahadevan L.
Tallinen T.
No associations
LandOfFree
Shock driven jamming and periodic fracture of particulate rafts does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Shock driven jamming and periodic fracture of particulate rafts, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Shock driven jamming and periodic fracture of particulate rafts will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-616079