SIZING LARGE HOLLOW MICRO-BALLOONS WITH THE PHASE DOPPLER INTERFEROMETER

A combined theoretical and experimental study has been conducted to ev aluate the effectiveness of using large, hollow micro-balloons as LDV seed particles. The study has focused on the ability of phase Doppler systems to size hollow micro-balloons, the ability of large micro-ball oons to respond to high frequency spatial and temporal flow field vari ations, and the overall advantages and disadvantages of using large mi cro-balloons instead of conventional LDV seed particles, such as very small water droplets or polystyrene latex (PSL) particles. This paper discusses the development of a theoretical phase Doppler response mode l for stratified spheres, the experimental facility, and the theoretic al and experimental results.