Influence of inherent particle characteristics on hopper flow rate

Shell Crystallization in Granular Hopper Flow

“…Interestingly, the results show that the flow rate is constant with the growing crystallized shell (Case A*) and decreases in the situation without the shell (Case C*), which questions the relationship between the flow rate and the roughness (or friction) of sidewalls. The flow rate in Case B* is smaller than that in both of Cases A* and C*, which verifies the influence of particle-particle friction reported in previous studies [22,23].…”

“…Similarly, DEM simulations by Gonzalez show that increasing wall roughness leads to a mass flow-funnel flow transition [21]. The discharge rate of a silo was reported to systematically decrease with increasing the surface roughness of the particles [22] or with increasing internal angle of friction of the granular material [23]. In the DEM simulations by Vidyapati the discharge rate decreased with increasing interparticle friction, but was insensitive to the wall friction [24].…”

Image analysis for morphology, rheology and degradation study of railway ballast: A review

“…For example, in [54], the base course performance is related with the particle morphology (form, angularity and surface texture). Another example in [77] proves the strong correlation between particle morphology with the drained friction angle and void ratio. The effects of particle morphology on ballast shear strength is studied in [78], demonstrating the correlation also exists in the ballast particles.…”

Gravitational discharge of fine dry powders with asperities from a conical hopper

“…The factors influencing the flow rate through a hopper mainly involved two aspects: the hopper geometry and particle property . The effects of hopper geometry (hopper angle, outlet size, hopper exit geometry, and fill height) and inherent particle property (particle size, size distribution, particle shape, angularity, surface roughness, actual density, bulk density, and porosity) on the flow behaviors and flow rate of particles in a hopper have been widely discussed. Uñac et al experimentally studied the flow of quartz particles with different size distributions through a silo with different hopper geometries.…”

“…Thus, a simple empirical correlation between the shape factor of particles by Beverloo's law and the actual shape of particles characterized by the shape index was proposed. However, as an important particle property, the surface roughness of particles is so difficult to define that its effect on the flow rate through a hopper has not been widely reported so far.…”