Flow and heat transfer characteristics of high temperature continuous rising bubbles

Abstract

In the movement process of continuous bubbles, different liquid flow state and initial temperature of bubble shave important influence on bubble movement and heat transfer. In this study, the flow and heat transfer characteristics of high temperature bubbles in normal temperature liquid are investigated. The rising process of and temperature of bubbles are studied by numerical simulation and compared with experimental results for verification. The results show that the shape, velocity and temperature of the bubble are affected by the initial position of the bubble. Because the closer the initial position of the bubble is to the bottom of the cylinder, the greater decrease of the bubble aspect ratio (w*),the faster decrease of bubble temperature, and the larger bubble velocity would be. The increase of the bubble diameter would mitigate the influence of liquid jet on the bubble motion. Finally, as the bubble surface tension increases, the liquid jet would have less influence on the bubble movement.