화학공학소재연구정보센터
HWAHAK KONGHAK, Vol.33, No.3, 353-359, June, 1995
압력요동을 이용한 밀도가 다른 이성분 혼합입자계의 최소유동화속도 측정
Measurement of the Minimum Fluidization Velocity of a Binary Mixture of Different Density Particle System Using Pressure Fluctuations
초록
내경 0.109m의 유동층에서 밀도차가 있는 모래와 PMMA의 홉합계에 대한 압력요동의 표준편차와 유속간의 선형회귀분석을 이용한 최소유동화속도 측정법의 적용성을 조사하였다. 이성분계 혼합물의 압력요동의 표준편차를 이용한 최소유동화속도를 flotsam의 분율과 입자크기에 따라 측정하고, 측정치를 타 연구자들의 이성분계식과 비교 검토하였다. 압력요동 표준편차 값의 선형회귀분석으로부터 최소유동화속도 결정에서 유속의 범위는 혼합도가 낮은 유속범위와 free bubbling영역 이상을 제외한 범위값이어야 하며, 이 유속범위에서 측정위치는 혼합이 양호한 층 중앙이 가장 적절하다.
The determination method of minimum fluidization velocity from the linear regression of standard deviation of pressure fluctuation according to air velocity was investigated with binary mixture of sand and PMMA in a 0.109m I.D. fluidized bed. The experiments were performed with change of operating variables such as the fraction of flotsam and particle size, and the measured values of the minimum fluidization velocity were compared with those obtained by the other researchers. The air velocity for this method has limited from well mixed region to freely bubbling region in a fluidized bed. The optimal measuring height of pressure fluctuations seems to be at middle levels on the axis of a bed, where the solid is well mixed.
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