Characteristics Measurement of Dense Bubbly Flow based on Laser Scanning

Bubbly flow is a typical flow pattern in gas-liquid two-phase flow, which has an important impact on industrial production. In this paper, combining laser scanning and high-speed photography, three-dimensional scanning of dense bubbly flow is carried out in a rectangular water tank. The bubble velocities in the horizontal and vertical directions are determined based on two-dimensional cross-correlation algorithm, and the latter shows a significantly higher velocity. Meanwhile, the variations of both velocities over time present a smooth fluctuation around the average value within a limited range. Besides, the bubble motion trajectories are established, and three-dimensional flow structure of dense bubbly flow is also reconstructed. The void fraction distribution is then investigated in various directions. Comparing the calculation results with the actual results, the relative error of void fraction is 6.58%.