Simulating soft granular silo flow in varying gravity

We present results of LAMMPS Molecular Dynamics simulations of 2D gravity-driven flows of ~30,000 soft uniform spheres through a vertical silo. We vary the gravitational field (g), elastic modulus of the particles (E), and silo outlet diameter (D) and measure the effects on mass flow rate, flow profiles, and microscale metrics such as granular temperature, looking in particular at the approach to clogging. We find a dimensionless combination of g, E, particle density ρ, and particle diameter p_d rescales the data for some measurements. We find the Beverloo equation describes the bulk flow many trials, but fails at extreme conditions. We also observe interesting pressure waves in the system.