ホッパー・といにおける粉体流量についての考察

抄録

In the flow of powder from a hopper with an inclined open channel, the flow rate increases as the opening height of the hopper outlet increases, and the increasing ratio of the flow rate diminishes suddenly as the outlet opening exceeds some critical height.
This behavior of the powder flow is interpreted in terms of a powder model in which the powder consists of homogeneous spherical particles and the frictional force is proportional to the height of the moving mass. The powder pressure at the outlet is assumed to be constant. The force balance between the powder pressure and the frictional force defines a critical opening height of the outlet. The flow rate increases monotonously with increasing height h of the outlet until h attains the critical value H_f. When h exceeds H_f, the increase in h does not contribute to further increase of the flow rate, but leads to a stationary mass beneath the moving layer.