Use of a simultaneous PLIF-PLIF technique to overcome optical problems in concentration measurements in two-phase bubbly systems

An experimental technique based on double planar laser-induced fluorescence (PLIF/PLIF) using two tracers for the measurement of the local concentration of liquid phase in a two-phase system with large bubbles is presented. Fluorescence emission intensity calibration was performed to validate the use of the laser and tracer combinations at each point in the images on two CCD cameras, separately. By normalizing the fluorescence emission intensity of the first tracer with a known concentration, with the fluorescence emission of the second tracer, the optical problems related to the bubbly two-phase flow were minimized. Concentrations measured in a bubbly system are shown to be in good agreement with the true concentration values