Abstract
This paper deals with the relationship between the porosity and the flow pattern of bulk solids in a bin.
The author first investgated the porosity of a bin which was achieved by central or peripheral feeding, and observed the flow pattern under each set of filling conditions during the discharge. From the results, it was found that the porosity of the bed achieved by peripheral feeding had a value considerably smaller than that in the case of central feeding. The flow pattern finally took on the form of a funnel.But when porosity increases in proportion to the rate of feeding, the result is mass flow. In such a case, a certain amount of time is required for particles to become detached from the walls of a bin and moved along with the flow and a pulsating pressure occurs near the hopper gate.
On the other hand, in the case of central feeding, the flow is a perfect mass flow in which nearly all particles along the walls of the bin move together at the commencement of the discharge.
