Modelling of Granular Flow on Micro- and Macroscopic Scales with Calibration Using Experimental and Numerical Setups

Discrete models are frequently used in research in the area of granular matter. While they provide detailed insights, powder simulations can suffer from high particle counts and immense computational times. Therefore, a macroscopic model is calibrated by experiments and discrete simulations to investigate powder discharge from a wedge-shaped silo for varying orifice sizes. Additional coupling with air flow inside the silo reveals that a compaction and a subsequent expansion of the particle bed during discharge causes pressure gradient forces at the outlet, influencing the mass flow rate. The magnitude of the pressure gradient is dependent on the filling level and the orifice size.