The Influence of the Packing Fraction on the Over-Pressure Ratio of Atomized Metal Powder Beds
1986 Volume 23 Issue 12 Pages 889-895
Details
1986 Volume 23 Issue 12 Pages 889-895
The influence of packing fraction on the over pressures has been studied at a rate of charging of about 0.04-47.19Kg/min, using atomized metal powders (Cu and Ni-Cr alloy) at a mean particle diameter range of 44.0.-127.0μm on a cylindrical bin sitting on its flat bottom.
The value of the packing fraction differed with the charging processes and rate. Especially, in the case of the dispersive charge, it in creased about 8% for powders larger than 89.5μm in mean particle diameter. As the packing fraction increased about 8%, the static wall pressure (Ps) was almost doubled, and the dynamic wall pressure (Pd) was markedly increased. The types of flow-patterns in the bin were determined by mass-flow when the packing fraction was smaller than 63.7% and by transition-flow when it was larger than 66.5%.
The results indicated that the over pressure increase as the flow-pattern types changed from mass-flow to transitional-flow due to decrease in charging rate.
