Velocity and Shear Stress Profiles of a Sheared Athermal System with Pins
ORAL
Abstract
We use molecular dynamics simulations to study a two-dimensional athermal, bidisperse system of particles with purely repulsive harmonic interactions. Via the motion of rough top and bottom walls composed of frozen particles, we shear the system at a constant rate. Energy is dissipated via a damping force
FD= -b (rij/rij .vij) rij/rij
The system furthermore has fixed degrees of freedom in the form of ‘pins.’ The size ratio of pins : small particle : large particle is 0.004:1:1.4. Pins are located on a square lattice. We study the microscopic and macroscopic properties of our system with and without pins in response to shearing. We show preliminary results for pressure and shear stress as function of shear rate and packing fraction. We show velocity and local shear stress profiles. Microscopically, we find that pins impede the propagation of velocity and shear stress far from the walls.Furthermore we study the time evolution of D2min and its relation to the contact number.
FD= -b (rij/rij .vij) rij/rij
The system furthermore has fixed degrees of freedom in the form of ‘pins.’ The size ratio of pins : small particle : large particle is 0.004:1:1.4. Pins are located on a square lattice. We study the microscopic and macroscopic properties of our system with and without pins in response to shearing. We show preliminary results for pressure and shear stress as function of shear rate and packing fraction. We show velocity and local shear stress profiles. Microscopically, we find that pins impede the propagation of velocity and shear stress far from the walls.Furthermore we study the time evolution of D2min and its relation to the contact number.
*We acknowledge the financial support from the National Science Foundation DMR-1905737 and DMR-1905474 and XSEDE/ACCESS allocations DMR-190064 and TRA-100004.
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Presenters
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AKM Sadman Mahmud
- Bucknell University