The bubble analysis of vertical fluidized-bed based on digital image technology

Gas-solid two-phase flow images in vertical fluidized-bed were obtained by High-speed photography system, and processed by digital image technology. Then the thesis about bubble shape variation characteristics, trajectory and bubble size variation when bubble rose in the vertical fluidized bed, and the bubble-centroid position and bubble-size variation when the bubble aggregate in the vertical fluidized-bed were acquired. The results show that the smaller the particles, the greater the air differential pressure, the more easily bubble presents cap-shaped when the bubble rises in the vertical fluidized-bed. The bubble spiral in the vertical fluidized-bed, and the smaller air differential pressure, the bigger particles, the more obvious the spiral. The bubble aggregation process is actually due to the large bubbles formed by attracting small bubbles. © 2015, Science Press. All right reserved.