Abstract：Effects of height to radius ratio on flow pattern and horizontal pressure in a silo filled with 6 mm glass beads discharged from wall outlet were investigated through discrete element method(DEM). The discharge time, horizontal pressure, discharge ratio and flow pattern obtained from DEM and test agreed well. Simulation results show that height to radius ratio greatly affects flow pattern and discharge speed. Funnel flow occurs in silos with low height to radius ratio. With the increase in height to radius ratio, the flow channel expands to the whole section of silo and the flow pattern becomes mass flow. The corresponding discharge speed increases apparently. The height to radius ratio has no influences on distribution of horizontal pressure in the flow channel, which follows a parabolic curve along silo height and is lower than that in static state.

Keywords: wall outlet discharge; discrete element method; height to radius ratio; wall horizontal pressure; flow pattern