检索结果-内蒙古大学图书馆

computational particle fluid dynamics simulation of gas–solid flow in a 3 MWth dual-circulation fluidized bed for chemical looping process

引用

Carbon Resources Conversion 2024年第4期7卷 43-53页

作者： Yankun Li Tuo Guo Xintong Guo Xiude Hu Qingjie Guo Shengzhong He Zimiao Zhou State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021NingxiaChina College of Chemical Engineering Qingdao University of Science&TechnologyQingdao 266042China Technology Innovation Center of Modern Chemical Engineering Ningxia PolytechnicYinchuan 750021China Ningxia Qinghua Coal Chemical Group Co. LtdWuzhong 751100China

Regulation of gas–solid flow is crucial for optimizing the operation efficiency of dual-circulating fluidized beds that are considered to be the most appropriate type of chemical-looping reactors. Herein, a computational particle fluid dynamics method was employed to simulate the gas–solid flow in a 3-MWth dual-circulating fluidized bed used for chemical-looping combustion and gasification. The influence of structural difference between units on particle residence time was determined. The multi-parameter control mechanism of pressure, particle circulation, and particle residence time in a whole-loop system was investigated. Results revealed that under stable particle circulation, the particle residence time in the fuel reactor is much longer than that in the air reactor. The axial forces on the particles are reduced upon increasing particle density and size, leading to particle accumulation in the dense-phase zone. When the particle properties are stable, increasing the fluidizing gas flow rates by the same proportion leads to identical pressure drops on the involved two loop seals, which cause symmetrical alterations in the particle circulation rate between the air and fuel reactors. The dual-circulating fluidized bed exhibits certain multi-condition adaptability, which is limited by the stock bin volume. Overall, this study is beneficial for effective and economical optimization of the operation of chemical-looping dual-circulating fluidized beds.

关键词： Chemical looping Dual-circulating fluidized bed computational particle fluid dynamics Gas-solid flow

来源：评论

学校读者我要写书评

暂无评论

computational particle fluid dynamics 3D simulation of the sorption-enhanced steam methane reforming process in a dual fluidized bed of bifunctional sorbent-catalyst particles

引用

POWDER TECHNOLOGY 2023年 424卷

作者： Di Nardo, Antonio Savuto, Elisa Calchetti, Giorgio Stendardo, Stefano ENEA Casaccia Res Ctr Energy Technol Dept Via Anguillarese 301 I-00123 Rome Italy

Sorption enhanced steam methane reforming (SE-SMR) is an efficient hydrogen production technology that combines steam methane reforming with CO2 capture. Reactions are shifted over their thermodynamic limits and hydrogen yield is enhanced, in more favorable thermodynamic conditions. Bifunctional sorbent-catalyst particles have been developed to assure stability over multiple cycles and to make the endothermic methane reforming and the exothermic CO2 capture completely integrated. Moreover, handling one granular material simplifies system management, reduces bed inventory and avoids the problem of segregation in case of two separated materials. The continuous and simultaneous operation of the process in a dual fluidized bed reactor (DFB), which combines a reformer and a calciner, for sorbent regeneration through high temperature calcination, increases productivity and allows a greater *** of this work is the 3D simulation of the SE-SMR process in a DFB reactor, by the computational particle fluid dynamics (CPFD) method of the Barracuda VR (R) software. The simulation results in terms of solid flow, pressure balance and particles segregation are reported. A post-processing routine has been written to charac-terize bubbles in the two fluidized beds. The effects of bed inventory, superficial velocity and steam to methane ratio on hydrogen purity and methane conversion are discussed in the paper.

关键词： Sorption enhanced steam methane reforming Calcium looping Bubbling fluidized beds computational particle fluid dynamics

来源：评论

学校读者我要写书评

暂无评论

Modeling of gas-solid flow in a CFB riser based on computational particle fluid dynamics

引用

Petroleum Science 2012年第4期9卷 535-543页

作者： Zhang Yinghui Lan Xingying Gao Jinsen State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China

A three-dimensional model for gas-solid flow in a circulating fluidized bed（CFB） riser was developed based on computational particle fluid dynamics（CPFD）.The model was used to simulate the gas-solid flow behavior inside a circulating fluidized bed riser operating at various superficial gas velocities and solids mass fluxes in two fluidization regimes,a dilute phase transport（DPT） regime and a fast fluidization（FF） *** simulation results were evaluated based on comparison with experimental data of solids velocity and holdup,obtained from non-invasive automated radioactive particle tracking and gamma-ray tomography techniques,*** agreement of the predicted solids velocity and holdup with experimental data validated the CPFD model for the CFB *** model predicted the main features of the gas-solid flows in the two regimes;the uniform dilute phase in the DPT regime,and the coexistence of the dilute phase in the upper region and the dense phase in the lower region in the FF *** clustering and solids back mixing in the FF regime were stronger than those in the DPT regime.

关键词： Gas-solid flow circulating fluidized bed computational particle fluid dynamics modeling hydrodynamics

来源：评论

学校读者我要写书评

暂无评论

A computational particle fluid-dynamics simulation of hydrodynamics in a three-dimensional full-loop circulating fluidized bed: Effects of particle-size distribution

引用

Particuology 2020年第2期18卷 134-145页

作者： Hang Zhang Youjun Lu State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049ShaanxiChina

A computational particle fluid-dynamics model coupled with an energy-minimization multi-scale(EMMS)drag model was applied to investigate the influence of particle-size distribution on the hydrodynamics of a three-dimensional full-loop circulating fluidized *** particle systems,including one monodisperse and two polydisperse cases,were *** numerical model was validated by comparing its results with the experimental axial voidage distribution and solid mass *** EMMS drag model had a high accuracy in the computational particle fluid-dynamics simulation of the three-dimensional full-loop circulating fluidized *** total number of parcels in the system(Np)influenced the axial voidage distribution in the riser,especially at the lower part of the *** numerical simulation results showed that axial segregation by size was predicted in the two polydisperse cases and the segregation size increased with an increase in the number of size *** axial voidage distribution at the lower portion of the riser was significantly influenced by particle-size ***,radial segregation could only be correctly predicted in the upper region of the riser in the polydisperse case of three solid species.

关键词： Circulating fluidized bed computational particle fluid dynamics particle-size distribution Energy-minimization multiscale model Three-dimensional full-loop simulation

来源：评论

学校读者我要写书评

暂无评论

Numerical simulation of gasification characteristics in a circulating fluidized bed biomass gasifiers

引用

BIOMASS CONVERSION AND BIOREFINERY 2025年第4期15卷 6269-6286页

作者： Wang, Junbiao Wu, Xuan Dong, Hui Pan, Yanan Chen, Huiling Inner Mongolia Univ Sci & Technol Sch Energy & Environm Baotou 014010 Peoples R China

In the computational particle fluid dynamics method, a numerical model of a three-dimensional circulating fluidized bed (CFB) air-water vapor mixture was established. This model facilitated an investigation of the characteristics of the biomass gasification process in a CFB gasifier. This study systematically examined the impact of variables such as fluidized gas velocity, gasification temperature, air equivalent ratio, and water vapor ratio on the spatial distribution characteristics of the gasification products. The results indicated that the increase in the fluidized gas velocity was correlated with a gradual reduction in the combustible gas concentration at the gasifier outlet. The increase in gasification temperature led to a decrease in CH4 content at both the furnace and gasifier outlets. Meanwhile, the CO and H2 content increased at these locations. A more balanced component distribution was observed at a gasification temperature of 1073.15 K. Moreover, increasing the air equivalent ratio resulted in a decrease in the flammable gas content at the furnace and gasifier outlet, enhancing a more uniform component distribution at an air equivalent ratio of 0.26.

关键词： computational particle fluid dynamics Circulating fluidized bed gasifier Biomass gasification Gas-solid two-phase flow

来源：评论

学校读者我要写书评

暂无评论

Desulfurization characteristics of slaked lime and regulation optimization of circulating fluidized bed flue gas desulfurization process--A combined experimental and numerical simulation study

引用

Chinese Journal of Chemical Engineering 2024年第9期73卷 163-175页

作者： Jing Chen Wenqi Zhong Guanwen Zhou Jinming Li Shasha Ding Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China Nanjing Iron and Steel United Co. Ltd.Nanjing 210035China

Circulating fluidized bed flue gas desulfurization(CFB-FGD) process has been widely applied in recent years. However, high cost caused by the use of high-quality slaked lime and difficult operation due to the complex flow field are two issues which have received great attention. Accordingly, a laboratory-scale fluidized bed reactor was constructed to investigate the effects of physical properties and external conditions on desulfurization performance of slaked lime, and the conclusions were tried out in an industrial-scale CFB-FGD tower. After that, a numerical model of the tower was established based on computational particle fluid dynamics(CPFD) and two-film theory. After comparison and validation with actual operation data, the effects of operating parameters on gas-solid distribution and desulfurization characteristics were investigated. The results of experiments and industrial trials showed that the use of slaked lime with a calcium hydroxide content of approximately 80% and particle size greater than 40 μm could significantly reduce the cost of desulfurizer. Simulation results showed that the flow field in the desulfurization tower was skewed under the influence of circulating ash. We obtained optimal operating conditions of 7.5 kg·s^(-1)for the atomized water flow, 70 kg·s^(-1)for circulating ash flow, and 0.56 kg·s^(-1)for slaked lime flow, with desulfurization efficiency reaching 98.19% and the exit flue gas meeting the ultraclean emission and safety requirements. All parameters selected in the simulation were based on engineering examples and had certain application reference significance.

关键词： Circulating fluidized bed flue gas desulfurization(CFB-FGD) Desulfurization characteristics computational particle fluid dynamics (CPFD)numerical simulation Operational optimization Gasesolid flow

来源：评论

学校读者我要写书评

暂无评论

Effects of riser geometry on gas-solid flow characteristics in circulating fluidized beds

引用

Particuology 2020年第2期18卷 205-217页

作者： Qiuya Tu Haigang Wang Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 10090China University of Chinese Academy of Sciences Beijing 100049China

The performance of a circulating fluidized bed strongly depends on its parameter settings,including that of riser *** this study,a laboratory-scale circulating fluidized bed with three different riser geometries(circular,square,and rectangular)that had the same cross-sectional area and height was operated under two static bed heights(20,and 35 cm).Electrical capacitance tomography was combined with differential pressure transducers and an optical-fiber probe to measure the solids'volume fraction,differential pressure fluctuations,and radial particle concentration *** particle fluid dynamics simulations were also *** results showed that single bubbles appeared in the bottom region of the circular and square risers and double bubbles in the bottom region of the rectangular *** autocorrelation of capacitance signals was periodic for the circular and square risers and non-periodic for the rectangular *** radial particle concentration profiles showed a single-core annulus structure in the circular and square risers,but a double-core annulus structure along the long side and single-core annulus structure along the short side in the rectangular *** entropy analysis showed that fluidization was less disordered and most predictable for the rectangular riser.

关键词： Circulating fluidized bed Riser geometry Static bed height Bubble shape Electrical capacitance tomography computational particle fluid dynamics

来源：评论

学校读者我要写书评

暂无评论

Characterization of the lateral gas–solid flow in a circulating fluidized bed boiler using simple mathematical model based on CPFD simulation data

引用

Chemical Engineering Science 2025年 314卷

作者： Shang, Manxia Jiang, Ling Zhao, Li Huang, Zhong Ke, Xiwei Lyu, Junfu Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Tsinghua University Beijing100084 China Shanxi Research Institute of Huairou Laboratory Taiyuan030006 China Beijing Huairou Laboratory Beijing101499 China

Operation safety, combustion efficiency, and pollutant emissions of circulating fluidized bed (CFB) boilers are significantly affected by the lateral gas–solid flow uniformity, which can be featured by the voidage (Εg) as well as particle lateral movement velocity (up). To obtain abundant data to support quantitative analysis and modeling, the gas–solid flow details in a 170 t/h CFB boiler were numerically simulated using the computational particle fluid dynamics (CPFD) method, which has been validated by field test data. Based on the original simulation data set, simple models for the prediction of lateral profiles of Εg and up were developed. In addition, both theoretical model and genetic algorithm-back propagation (GA-BP) neural network were applied to predict the lateral solids movement behavior. Results show that both two models exhibit excellent prediction accuracy with the coefficient of determination (R2) exceeding 0.99. While the theoretical model derived from physical equations is relatively simple and has a clear physical meaning. All the simple models developed in this paper can be embedded into the overall CFB mathematical model framework, facilitating the comprehensive analysis of the operational characteristics for large-scale industrial CFB boilers. © 2025

关键词： Circulating fluidized bed computational particle fluid dynamics Lateral gas–solid flow Lateral voidage Neural network particle lateral movement velocity

来源：评论

学校读者我要写书评

暂无评论

Experimental and CPFD study of gas-solid flow in a cold pilot calciner

引用

POWDER TECHNOLOGY 2018年 340卷 99-115页

作者： Nakhaei, Mohammadhadi Hessel, Christian Evald Wu, Hao Grevain, Damien Zakrzewski, Sam Jensen, Lars Skaarup Glarborg, Peter Dam-Johansen, Kim Tech Univ Denmark Dept Chem & Biochem Engn Lyngby Campus DK-2800 Lyngby Denmark FLSmidth AS Cement R&D Vigerslev Alle 77 DK-2500 Valby Denmark

Experimental characterization and computational fluid particle dynamics (CPFD) simulations of a cold pilot scale cement calciner were carried out to investigate the dispersion and heating of cold cement raw meal particles in the hot gas flow. During the experiments, the gas velocity and temperature were measured at different locations upstream and downstream of the place where the particles were fed to the calciner. The simulations were carried out using Eulerian-Lagrangian approach together with the Multi-Phase particle-In-Cell (MP-PIC) method, based on the commercially available Barracuda Virtual Reactor (R) 17.1.0 software. For the particle-free flow, it was shown that the grid-independent velocity profiles predicted from the simulations are in proper agreement with the measured values. For the particle-laden flow, the simulation results from two drag models of EMMS and Gidaspow were compared with the gas temperature measurements and visual observations. The simulation results from the Gidaspow model exhibited an over-prediction of the amount of falling particles to the upstream regions. Both drag models exhibited a local minimum temperature region at a location slightly different from the measured one in a cross-section close to the particle feed position. For the Gidaspow model, a second low gas temperature region was observed at the opposite position of the particle feed that was not detected by the measurements. Overall, it is concluded that the Barracuda Virtual Reactor (R) software is able to capture the particle dispersion and gas-solid interactions in the studied pilot-scale calciner and the EMMS drag model is more reliable for prediction of the gas-solid flow. (C) 2018 Elsevier B.V. All rights reserved.

关键词： Cement calciner Gas-solid flow computational particle fluid dynamics Drag model Heat transfer

来源：评论

学校读者我要写书评

暂无评论

3D CPFD simulation of gas-solids flow in the high-density downer with FCC particles

引用

POWDER TECHNOLOGY 2020年 373卷 384-396页

作者： Wu, Yingya Shi, Xiaogang Liu, Yancong Wang, Chengxiu Gao, Jinsen Lan, Xingying China Univ Petr State Key Lab Heavy Oil Proc Beijing 102249 Peoples R China

The gas-solids flow in high-density downers with FCC particles was simulated by computational particle fluid dynamics (CPFD) approach. A drag model was proposed based on the equivalent diameter of cluster with the analysis of force balance on particle cluster. A global sensitivity analysis method was used to analyze the influencing factors of cluster size. The drag model was incorporated into the three-dimensional (3D) CPFD approach to simulate the gas-solids flow in two different downers operating at various conditions. 3D CPFD simulation provided detailed trajectories and distributions of solids. Good agreements of the predicted solids holdup and velocity with experimental data were achieved at both low and high-density conditions, which verified the rationality and applicability of the present drag model considering the characteristics of particle cluster in the downer. Finally, the flow and clustering behavior in the high-density downer were adequately analyzed and compared with that in low-density downer. (C) 2020 Elsevier B.V. All rights reserved.

关键词： Downer High-density Cluster Drag model computational particle fluid dynamics

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：