Dynamical weakening by fluidization under oscillatory viscous flows

Passive swimming in viscous oscillatory flows.

Fluid-based locomotion at low Reynolds number is subject to the constraints of Purcell's scallop theorem: reciprocal shape kinematics identical under a time-reversal symmetry cannot cause locomotion. In particular, a single degree-of-freedom scallop undergoing opening and closing motions cannot swim. Most strategies for symmetry breaking and locomotion rely on direct control of the swimmer's sh...

Title Dynamic Weakening by Acoustic Fluidization during Stick -Slip Motion

Dynamic Weakening by Acoustic Fluidization during Stick-Slip Motion.

The unexpected weakness of some faults has been attributed to the emergence of acoustic waves that promote failure by reducing the confining pressure through a mechanism known as acoustic fluidization, also proposed to explain earthquake remote triggering. Here we validate this mechanism via the numerical investigation of a granular fault model system. We find that the stick-slip dynamics is af...

Granular Flows and Gas-fluidization

This paper examines the roles that granular flow theory might play in the modeling the solid-phase stresses in fluidized beds. It begins with a discussion of the historical limiting cases of the quasistatic and rapid-flow regimes. It then reviews the elastic granular theories that unify those two regimes. Finally it shows that measurements of solid-phase pressures cannot be explained by commonl...

Convection and fluidization in oscillatory granular flows: The role of acoustic streaming.

Convection and fluidization phenomena in vibrated granular beds have attracted a strong interest from the physics community since the last decade of the past century. As early reported by Faraday, the convective flow of large inertia particles in vibrated beds exhibits enigmatic features such as frictional weakening and the unexpected influence of the interstitial gas. At sufficiently intense v...