Experimental study on the discharge characteristics with downward moving bubbles in a two-dimensional aerated hopper. (2nd February 2021)

• Record Type: Journal Article
• Authors: Guo, Xiaolei; He, Jimin; Lu, Haifeng; Liu, Haifeng
• Is Part Of: Chemical engineering science. Volume 230(2021)
• Publication Date: 2021-02-02
• Subjects: Aerated hopper -- Powder discharge -- Bubble behaviour; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2020.116212
• Languages: English
• ISSNs: 0009-2509

Abstract

Highlights: Three typical discharge states of the aerated hopper were proposed. The minimum aeration gas velocity for downward moving bubble was obtained. The effects of downward moving bubbles on the discharge were discussed. Abstract: The characteristics of bubble behaviors during powder discharge process in a two-dimensional aerated hopper were studied by a high-speed camera system. The experimental results show that there are three typical discharge states with the rise of the aeration gas velocity. Correspondingly, three critical aeration gas velocities were all tested including the minimum bubbling, the maximum discharge rate and the minimum bubbling for downward moving to the outlet. The downward moving bubble formation frequency increases with the growth of gas velocity, and its proportion finally stabilizes at about 90%. This tendency is similar with that of the discharge rate. Resultantly, the bubble formed in the powder bed can promote the discharge by provide the interstitial gas to the powder bed, but plays a negative role as it gets larger and substantially moves downward.