The Behavior Of A Single Bubble Rising In A Complex Shaped Channel Containing A Liquid

The research on the behavior of bubble movement in the gas-liquid two-phase, which exists in nature and many engineering fields, is involved in chemical, energy, power and petroleum engineering industries. However, due to limitations of knowledge and experimental equipment, the bubbles’behaviors across the pipe wall in the liquid is far from comprehensive. Given above situation, on the basis of the National Natural Science Foundation Project, employing high-speed photography and computer image processing technology, the rising single bubbles interacting with the tube wall was studied. The laws of deformation of the bubbles between the tube bundles, rebounding, rolling and adhesion of the bubble nears the tube bundle were stated preliminarily. This research mainly includes the following aspects:1. The experimental apparatus was self-designed. The main part of the experimental observation recorded by high-speed camera was made of the Lucite glass; High definition images could be obtained by using the iodine-nickel filament lamp as lighting source through a comparative analysis of multiple light sources. The release of single bubbles would be interval uniform by setting up the pump and micro-regulating valve.2. Canny edge detection algorithm, the best ladder edge detection algorithm, was selected as the key tool to deal with the images, with the Image-Pro Plus6.0as an auxiliary tools.3. The law of the trajectory, deformation, rotation angle, velocity, Re number and drag coefficient of the bubbles during the rising course were obtained under different working conditions. The rebound of the bubble in the tube wall, adhesion, rolling and sliding are compared and analyzed during the rising course.4. The experimental results show that:as for a single bubble in the liquid, it was spiraling up with the rolling and spinning, which was effected by arrangement mode of the tube bundle; the bubble velocity, Re number and drag coefficient increased as the Eo number increased, and in the medial stage, the minimum value and maximum value appeared alternately; the dynamic parameter of the bubble reduced as vertical tube spacing increased; the bubbles sprayed from different injection position achieved the same state. But in the initial and the middle stage, the shape, the rotating angle, velocity et al were also affected by the injection position, and the bubble was mainly affected by the first tube contacted in the rising course.