抄録
The authors explained the mechanisms that coused the reciprocating bubble migration with flip-flop phenomenon in a diamond-shaped cylinder bundle. However, it lacks sufficient, quantitative explanation due to comploxity in these flows. An experimantal study is perfomed to determine flow characteristics in the diverging-flow region with flip-flop phenomenon inside diamond-shaped cilinder bundles. The velocity variations in their flow fields with different cross-sectional areas were measured using two-dimensional laser Doppler velocimetry(LDV). The oscillation characteristics of flip-flop flow inside diamond-shaped cylinder bundles with different flow passages are clarified.