Spatiotemporal Structure Analysis on a Bubbly Jet Flow by using POD

摘要

Bubbly flows are complicated flows because bubbles are deformable and the bubblc-bubble interactions act in local area among a lot of bubbles. Such flow in liquid phase disturbed by each bubble is called "pseudo turbulence". A PIV is most effective tool to measure such bubbly flow because of multi-dimensional measurement and simultaneous acquisition of a lot of bubbles and surrounding flow. Recently Dynamic PIV system consisted of high-speed camera and highrepetition laser is developed, and it is possible to capture time-serial images with higher resolution. In this paper, these liquid phase velocities near jet inlet are calculated by PTV and rearrangement method, and then we show some spatio-temporal characteristic analyzed by POD (Proper Orthogonal Decomposition) method.