Evaluation of fluidized particle flow by measurement of apparent buoyancy

Fluidized particle flow is evaluated by the apparent buoyancy acting on a sphere in the fluidized bed. The apparent buoyancy is simply obtained as follows: the weight of the lead sphere is measured at various positions in the fluidized glass beads and the difference between the weight in the fluidized bed and that in the atmosphere is regarded as the apparent buoyancy. The particle flow coefficient α is calculated using the distribution of the apparent buoyancy to show the strength of the particle flow. Measurements are carried out varying the superficial air velocity, the height of the bed, the particle size and the sphere size, and the distributions of the apparent buoyancy and the values of α are compared. It is found that the fluidized particle flow can be simply evaluated by the distributions of the apparent buoyancy and the values of α, and that the difference of the particle flow under various experimental conditions is proved by them, e.g. the circulating particle flow becomes strong as the superficial air velocity increases.