2133 レーザーフォーカス変位計による FEP マイクロチャンネル内液膜界面の計測  [in Japanese] Measurement on Liquid Film Interface in FEP-Microchannels Using Laser Focus Displacement Meter  [in Japanese]

This paper presents a new method for measuring the interface of a liquid film in microchannels using a laser focus displacement meter (LFD). To prevent the tube wall signal from disturbing that of the gas-liquid interface, a fluorocarbon tube with water box was used; the refraction index of this device was the same as that for water. Simultaneous measurements of the interface in fluorocarbon tubes of 0.5 and 1mm I.D. using the LFD and a high-speed video camera with a microscope showed that the LFD could measure the interface of a liquid film with high spatial and temporal resolution during annular, slug, and piston flow. The data also clarified the existence of a thin liquid film less than 1μm in thickness in slug and annular regimes.