🌾 Silo Hopper: Beverloo Discharge, Janssen Pressure and Arching Limit (2D)

Side view of a grain bin with a conical hopper, showing the level falling at a steady rate when the outlet is wide enough and an arch blocking the flow when a cohesive powder meets a narrow outlet. Set the bin size, outlet, grain size, density, wall friction, cohesion and hopper angle, and see the discharge rate, time to empty, the pressure at the base and the smallest outlet that does not arch. Janssen pressure, Beverloo scaling, the arching limit and the discharge time are checked numerically, with four in-page numerical checks.