BUBBLE-SIZE AND VELOCITY-MEASUREMENT IN GAS-LIQUID SYSTEMS - APPLICATION OF FIBER OPTIC TECHNIQUE TO PILOT-PLANT SCALE

A new fiber optic probe was developed for the detection and measuremen t of bubble sizes and velocities in a gas-liquid column. The probe is made of a single 1 mm plastic fiber with a sharp wedge tip. The calibr ation was carried out on a laboratory scale unit using a cine-photogra phic technique to verify the measurements. Bubble velocities were calc ulated using two identical parallel fibers and the cross-correlation t echnique. With the velocities and the passage time determined, it was then possible to determine the bubble diameter. Bubble diameters were within 10% of the measurements obtained with the cine-photographic tec hnique. After calibration, measurements were carried out on a pilot sc ale unit.