粉体の排出に伴う動的圧力変動について

抄録

Using a model of the cylindrical vessel, the authors measured the lateral dynamic pressures at nine different heights.
We showed in these works that the dynamic pressures which occurred durring discharge through the orifice are much greater than those of initial static conditions.
The present report mentions about the maximum wall pressure measurements and the fundemental flow-patterns, and obtained the following results.
(1) The characteristic wave of the dynamic pressures is classified into four large groups.
(2) As soon as discharging cu-powder, the maximum impact pressures occurred at each measuring positions heigher than the 40mm from the orifice plate.
(3) When cu-powder in a vessel is discharging, the internal flow accompanies by the micro bridging which is repeated by 1/500-1/600sec and the macro bridging which is repeated by 1/50sec.
(4) On the wall pressure distribution, the large pressure value was observed near the measuring position of 30mm and 150mm.
(5) In the case of 4mm^φ of different orificies, 2mm^φ, 3mm^φ, 4mm^φ, 5mm^φ, 6mm^φ, the wall pressure was minimum, when the 34mm^φ vessel was used.
(6) In the case of the 34mm^φ of different vessel, 17mm^φ, 24mm^φ, 34mm^φ, 60mm^φ, the wall pressure was maximum, when the 3mm^φ orifice was used.