Hydrodynamic Modeling of Gas–Solid Bubbling Fluidization Based on Energy-Minimization Multiscale (EMMS) Theory

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• 作者：Xinhua Liu ; Yuefang Jiang ; Cenfan Liu ; Wei Wang ; Jinghai Li
• 刊名：Industrial & Engineering Chemistry Research
• 出版年：2014
• 出版时间：February 19, 2014
• 年：2014
• 卷：53
• 期：7
• 页码：2800-2810
• 全文大小：534K
• ISSN：1520-5045

文摘

Hydrodynamic modeling of gas鈥搒olid bubbling fluidization is of significance to the development of gas鈥搒olid bubbling reactors since it still remains at the stage of experimental and empirical science. As is the role of particle clusters in gas鈥搒olid fast fluidization, gas bubbles characterize the structural heterogeneity of gas鈥搒olid bubbling fluidization, and their evolution is mainly subject to the constraints of the stability and boundary conditions of the system. By considering the expansion work of gas bubbles against the normal pressure stress in the emulsion phase, an improved necessary stability condition is proposed to close a gas鈥搒olid bubbling model. Applying the upgraded gas鈥搒olid bubbling model at the scale of vessels, the steady-state hydrodynamics of gas鈥搒olid bubbling fluidization can be reproduced without introducing bubble-specific empirical correlations such as for diameter and/or acceleration. The unified modeling of the entire gas鈥搒olid fluidization regime from bubbling to fast fluidization is performed by integrating the upgraded gas鈥搒olid bubbling model with the original energy-minimization multiscale (EMMS) model. Incorporating the upgraded gas鈥搒olid bubbling model into commercial computational fluid dynamics (CFD) software at the scale of computational cells, the unsteady-state simulation of gas鈥搒olid bubbling fluidization is realized with a higher accuracy than that based on homogeneous drag models.