Manabu Iguchi
Faculty of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka, 565, Japan
Tsuneo Kondoh
Department of Materials Science and Processing, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565, JAPAN
Zen-Ichiro Morita
Department of Materials Science and Processing Osaka University, Osaka, Japan
Tomomasa Uemura
Faculty of Engineering, Kansai University, 3-3-35 Yamate, Suita-shi, Osaka, 564 Japan
Fujio Yamamoto
Faculty of Engineering, University of Fukui, Fukui 910-8507, Japan
A vertical bubbling jet was generated in a cylindrical bath by injecting air from a single-hole centric nozzle. The axial and radial velocity components of bubble and liquid in the vertical bubbling jet were measured simultaneously using an electro-resistivity probe and a two-dimensional laser Doppler velocimeter. The output signal of the LDV was processed on a personal computer at a sampling frequency of 2kHz. Hold signals were eliminated. Discrimination of the bubble and liquid velocities was made by referring to the output signal of the electro-resistivity probe. The accuracy of the present velocity measurement of bubbles and liquid was found to be satisfactory from a comparison with results obtained using an image processing technique for high-speed video pictures and a two-dimensional electro-resistivity probe.