鉛直管内穀粒流動化の終端速度

It is necessary to know the characteristics of grain when grain is transferred and processed. In this research, in order to clarify the fundamental flow characteristics of grain, the flow state in a vertical pipe was investigated. Brown rice, BB shot (pellets) "BB's" and soybean were fluidized by the air style. We determined minimum fluidization velocity and terminal velocity, recorded the flow state, and observed the flow state with a video camera. The results of the experiment were as follows: 1) Minimum fluidization wind velocities were 1.6-2.1m/s in soybean, and 1.2-1.7m/s in BB's. This might be because of the shapes of soybean and BB's. 2)A fountain state appeared in brown rice, but not in either soybean or BB's. This might be because of the shapes of soybean and BB's. 3)Terminal velocity was 6.8m/s in brown rice, 9.5m/s in BB's, and 12.2m/s in soybean respectively.

穀粒を輸送し，調製加工する場合には，その特性を知る必要がある．本研究は，鉛直管内における流動状態を調べることにより，穀粒の基本的流動特性を明らかにする目的で，玄米，BB弾，大豆を空気流によって流動化させて，流動化開始風速と終端速度を求め，その流動状態をビデオカメラで記録して観察した．その結果から：1.流動化開始風速は，大豆が1.6～2.1m/ｓ，BB弾は1.2～1.7m/ｓ，玄米は0.6～1.1m/ｓの範囲にあった．2.玄米に噴水状態が現れたが，大豆とBB弾に噴水状態がなかった．これはBB弾と大豆の形状が球あるいは球に近いためであると考えられた．3.終端速度を測定した結果，玄米が6.8m/ｓ，BB弾は9.5m/ｓで，大豆は12.2m/ｓであることが分かった