Discharge flow and dynamic stress of coal particles in rectangular silos with pyramidal hopper

To study the particle discharge flow and dynamic stresses in silos, an overhead rectangular silo with pyramidal hopper was designed and tested. The inclination of the discharge hopper and the size of the rectangular cross-section are adjustable. Based on inclinations of 45°, 55°, 65° for the pyramidal hopper, nine groups of discharge flow experiments were performed by using coal particle diameters of < 3 mm, 3–6 mm, and 3–13 mm. The results showed that the smaller dry coal particles performed better; furthermore, the height-to-diameter ratio of the straight silo and the inclination of the discharge hopper affected the flow of coal particles. The distribution of the dynamic side stress in the middle silo plate during discharge was indirectly tested. The results showed that the maximum stress appeared around the middle of the straight silo. During discharge, the lateral stresses in the silos were larger than the static stresses, with obvious overstresses in the middle and upper parts of the silos. D...