Structural Design and Performance of a Jet-Impinging Type Microbubble Generator
Yun Shuai, Xinyan Wang, Zhengliang Huang, Yao Yang, Yao Yang, Jingyuan Sun, Jingdai Wang, Yongrong Yang, Yongrong Yang
Abstract
A jet-impinging type microbubble generator is designed, including a liquid nozzle and a gas nozzle with the disc-baffle closely arranged along the same axis. When the disc-baffle diameter is greater than the jet width at the gas nozzle position, the impingement zone and radial wall-jet region are formed, thereby promoting the generation and dispersion of microbubbles. As the dissipation rate in the impingement zone increases, the mean bubble diameter decreases, and the number fraction of microbubbles increases. The bubble radial dispersion width is dependent on the radial wall-jet velocity and the time for the bubble to follow the radial wall-jet. Reducing the surface tension is beneficial to the generation of microbubbles but has little effect on the state or width of the microbubble dispersion. Empirical correlations for predicting the d32 and dispersion width are proposed, and the relative error is less than 20%. The results show that the jet-impinging type microbubble generator has better energy efficiency than most bubble generating systems reported in the literature.