Powder Handling in Microgravity
-Part 1. Hypogravitational Centrifugal Fluidized Beds-

　Experiments were performed with a 94mm diameter, 5mm high centrifugal bed operating in hypogravity field less than one g₀ with atmospheric, room temperature air with 98μm and/or 1200μm glass beads materials under microgravity conditions. Visual observations showed that the bed became fluidized similarly as the familiar gravitational or hypergravitational bed, and the bubble was found to generate in the bed. The data showed that no significant change of the initial bubble diameter was observed in the range of the hypogravity of 0.1g₀ to 0.5g₀. The segregation behavior of large glass beads of 1200μm was also examined and the degree of segregation increased rapidly with hypogravity up to 0.1g₀ and with air flow rate above initial fluidization of 98μm small particles.