LAUSR

Abstract The flow pattern, mass flow rate, and stability of discharge rate of conical hoppers and hyperbolic hoppers with different diameters and initial inclination angles were studied by the finite element method(FEM). The results showed that the flow pattern of conical hoppers changed as the Jenike criterion when the half-angle was about 35° while hyperbolic hoppers did not follow it. Usually, the mass flow rate of the hyperbolic hopper was higher than the conical hopper. Avalanche and arching influence the stability of discharge rate. When they exist at the same time, the stability of discharge rate will be improved, and there was an equilibrium point in their interaction so that the stability of discharge rate was the largest. For conical hoppers, the stability of discharge rate reached the best when the initial inclination angle was about 35°, while for hyperbolic hoppers the initial inclination angle was about 25°-35°.