Investigation of flow hydrodynamics and regime transition in a gas-solids fluidized bed with different riser diameters

被引：57

作者：

Qiu, Guizhi ^{[1
,2
]}

Ye, Jiamin ^{[1
]}

Wang, Haigang ^{[1
]}

Yang, Wuqiang ^{[3
]}

机构：

[1] Chinese Acad Sci, Inst Engn Thermophys, Beijing 100190, Peoples R China

[2] Univ Chinese Acad Sci, Beijing 100190, Peoples R China

[3] Univ Manchester, Sch Elect & Elect Engn, Manchester M13 9PL, Lancs, England

来源：

CHEMICAL ENGINEERING SCIENCE | 2014年 / 116卷

基金：

英国工程与自然科学研究理事会; 中国国家自然科学基金;

关键词：

Flow regime; Electrical capacitance tomography; Differential pressure; Solids volume fraction; Bubble characteristic; Transition velocity; ELECTRICAL CAPACITANCE TOMOGRAPHY; IMAGE-RECONSTRUCTION ALGORITHM; VOLUME CONCENTRATION; BUBBLE; SIMULATION; VELOCITY; BEHAVIOR;

D O I：

10.1016/j.ces.2014.05.006

中图分类号：

TQ [化学工业];

学科分类号：

0817 ;

摘要：

It is important to understand the flow hydrodynamics behavior of a circulating fluidized bed (CFB) reactor for efficient operation. The objective of this research is to identify and characterize the flow regimes in a fluidized bed with different riser diameters. For this purpose, electrical capacitance tomography (ECT) combined with pressure measurement has been used to investigate the flow characteristics and flow regime transitions. Experiment was carried out in a cold gas solids fluidized bed to investigate the flow regimes and the transition velocities. Three risers of different diameter, 10, 12 and 15 cm, are designed and used for comparison. A twin-plane ECT sensor and a differential pressure transducer are used to obtain the solids volume fraction and differential pressure in the bottom region. Different flow regimes including bubbling, slugging and turbulent flow regime were formed with two distinct transition velocities. The flow characteristics are investigated in terms of solids volume fraction, bubble diameter and bubble rising velocity. The transition velocities are compared based on the ratio of the static bed height to bed diameter (H-st/D) and the measured position (i.e. the axial position and radial position). (C) 2014 Elsevier Ltd. All rights reserved.

引用

页码：195 / 207

页数：13

共 42 条

[1]

Azzi M., 1991, USE MOMENTUM PROBE G, P189

[2] Flow structure in a fast fluidized bed [J].

Bai, D ;

Shibuya, E ;

Masuda, Y ;

Nakagawa, N ;

Kato, K .

CHEMICAL ENGINEERING SCIENCE, 1996, 51 (06) :957-966

[3] Characterization of gas fluidization regimes using pressure fluctuations [J].

Bai, D ;

Shibuya, E ;

Nakagawa, N ;

Kato, K .

POWDER TECHNOLOGY, 1996, 87 (02) :105-111

[4] Simulation of air flow in the typical boiler windbox segments [J].

Bhasker, C .

ADVANCES IN ENGINEERING SOFTWARE, 2002, 33 (11-12) :793-804

[5] The dynamic calibration of an electrical capacitance tomography sensor applied to the fluidized bed drying of pharmaceutical granule [J].

Chaplin, G ;

Pugsley, T ;

van der Lee, L ;

Kantzas, A ;

Winters, C .

MEASUREMENT SCIENCE AND TECHNOLOGY, 2005, 16 (06) :1281-1290

[6] Gas and solids between dynamic bubble and emulsion in gas-fluidized beds [J].

Cui, HP ;

Mostoufi, N ;

Chaouki, J .

POWDER TECHNOLOGY, 2001, 120 (1-2) :12-20

[7]

DARTON RC, 1977, T I CHEM ENG-LOND, V55, P274

[8]

Davidson J.F., 1985, FLUIDIZATION, P1985

[9]

Davidson JF., 1963, Fluidization Particles

[10] CFD analysis of air distribution in fluidised bed equipment [J].

Depypere, F ;

Pieters, JG ;

Dewettinck, K .

POWDER TECHNOLOGY, 2004, 145 (03) :176-189

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