Velocity Measurement of Gas/Liquid Interface Using PIV Technique
Details
In the ordinary PIV measurement, digital images are gotten from scattering light of tracer particles and moving distance of the particles is measured. When the PIV is applied to the gas/liquid two-phase flow which has high void ratio, however, the velocity measurement is very difficult because the scattering light from the gas/liquid interface is strong compared with from the particles. The one of important factors is the luminance adjustment of the scattering light in the PIV measurement of gas/liquid two-phase flow. In the present study, the information of high-level luminance is utilized actively to measure the moving velocity of the gas/liquid interface. By the adjustment of the contrast and the brightness of original digital images obtained from the PIV measurement, the information of the high-level luminance is extracted and the shape of the gas/liquid interface can be distinguished. As the large-scale deformation and high-speed movement are included in the motion of the interface, high resolution in both time and space has to be required to get the digital images. By the utilization of the high-speed camera and the luminance adjustment, the measurement of the moving velocity of the gas/liquid interface was succeeded.
