CFD study of exit effect of high-density CFB risers with EMMS-based two-fluid model

CORC > 过程工程研究所 > 中国科学院过程工程研究所 > 多相复杂系统国家重点实验室

	CFD study of exit effect of high-density CFB risers with EMMS-based two-fluid model
	Zhao, Bidan1,2 ; Zhou, Quan 1,2; Wang, Junwu1 ; Li, Jinghai 1
刊名	CHEMICAL ENGINEERING SCIENCE
	2015-09-29
卷号	134 期号:SEP 页码:477-488
关键词	Fluidization Multiphase flow Mesoscale structures Stability Particulate processes Powder technology
ISSN号	0009-2509
英文摘要	It has been widely recognized that the exit geometry of circulating fluidized bed (CFB) risers may have significant effects on the hydrodynamics of gas-solid flow. However, a systematical study of exit effect is still lack after extensive experimental studies, possibly due to the fact that systematical modification of exit geometry in experimental study is an expensive and time-consuming task. In this study, after further validation of the recently developed EMMS-based two-fluid model (Wang et al., 2012. Chem. Eng. Sci. 75, 349-358; Zhou et al., 2014. Chem. Eng. Sci. 107, 206-217), the model is used to systematically investigate the effect of exit geometry of high-density CFB risers, fully taking the advantage that bed geometry can be easily modified in computational fluid dynamics study. It is shown that (i) the type of exit has a significant effect on hydrodynamics, the use of abrupt exit results in an increased solids concentration, not only in the immediate vicinity of the exit but also for a considerable distance down to the riser; (ii) the cavity height of abrupt exit, the curvature diameter of smooth exit and the length of the horizontal tube connecting the exit and the primary cyclone only have a minor effect or have no influence on the bed hydrodynamics of the studied risers; (iii) more importantly, the decrease of the diameter of abrupt exit tube results in a remarkable increase of solids holdup, the symmetry of radial solids concentration near the exit can also be enhanced significantly. However, in case of smooth exit, the diameter of the exit tube has no effect on the bed hydrodynamics at all. All of those results are in agreement with conclusions obtained from previous experimental studies, thus offering further validation of the EMMS-based two-fluid model for modelling heterogeneous gas-solid flow. (C) 2015 Elsevier Ltd. All rights reserved.
WOS标题词	Science & Technology ; Technology
类目[WOS]	Engineering, Chemical
研究领域[WOS]	Engineering
关键词[WOS]	CIRCULATING FLUIDIZED-BED ; SQUARE CROSS-SECTION ; GAS-SOLID FLOWS ; FULL-LOOP ; SIMULATION ; HYDRODYNAMICS ; PARTICLES ; PATTERNS ; GEOMETRY ; VELOCITY
收录类别	SCI
语种	英语
WOS记录号	WOS:000359029200045
内容类型	期刊论文
源URL	[http://ir.ipe.ac.cn/handle/122111/19421]
专题	过程工程研究所_多相复杂系统国家重点实验室
作者单位	1.Chinese Acad Sci, Inst Proc Engn, State Key Lab Multiphase Complex Syst, Beijing 100190, Peoples R China 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China
推荐引用方式 GB/T 7714	Zhao, Bidan,Zhou, Quan,Wang, Junwu,et al. CFD study of exit effect of high-density CFB risers with EMMS-based two-fluid model[J]. CHEMICAL ENGINEERING SCIENCE,2015,134(SEP):477-488.
APA	Zhao, Bidan,Zhou, Quan,Wang, Junwu,&Li, Jinghai.(2015).CFD study of exit effect of high-density CFB risers with EMMS-based two-fluid model.CHEMICAL ENGINEERING SCIENCE,134(SEP),477-488.
MLA	Zhao, Bidan,et al."CFD study of exit effect of high-density CFB risers with EMMS-based two-fluid model".CHEMICAL ENGINEERING SCIENCE 134.SEP(2015):477-488.