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类型 基础研究 预答辩日期 2017-12-04
开始(开题)日期 2014-02-27 论文结束日期 2017-11-07
地点 热能所一楼会议室 论文选题来源 973、863项目     论文字数 8 (万字)
题目 非球形颗粒喷动床流体动力学特性及放大规律研究
主题词 喷动床,非球形颗粒,放大特性,CFD-DEM
摘要 喷动床作为典型的流态化设备目前已广泛应用于农业、食品、制药、能源、环保、化工、核燃料等众多领域,如干燥、混合、造粒、包衣涂层等多种物理工艺过程,同时在煤气化、生物质制合成燃料、油页岩热解、铁矿石还原、焦炭活化、石油催化裂化等诸多热化学工艺中也显示了其诱人的前景。然而目前对喷动床复杂气固流动特性的认识还远远不能满足日益广泛的应用要求,尤其是对非球形颗粒系统在喷动床中动力学特性、气固相互作用机理以及喷动床放大技术掌握不够,以至于在设备放大设计、结构参数优化等方面都遇到一定的困难。 本文基于试验和数值模拟手段,对非球颗粒喷动床动力学特性及放大规律进行了深入研究。 构建了非球形颗粒喷动床试验系统,以具有典型非球形状特征的柱状颗粒为研究对象,实验揭示了非球颗粒/床料二元颗粒系统的喷动动力学特性。发现了二元颗粒系统喷动与混合实时同步耦合的行为特点,获得了二元颗粒系统行为与关键参数随操作条件的变化规律和控制机制,提出了床料主导型和非球颗粒主导型两种不同的非球颗粒喷动系统类型。 发展和改进了喷动床CFD-DEM模拟方法。运用几何元素组合方法构建具有真实形状的柱状颗粒,全面解析了柱状颗粒平面、曲面以及边线之间多种接触情形和接触力计算,改进了适用于柱状颗粒的气固曳力模型,构建了柱状颗粒CFD-DEM数理模型,率先在CPU+GPU计算平台上实现“气相湍流+真实柱状颗粒+喷动”的CFD-DEM数值模拟,从颗粒尺度分析了颗粒形状对喷动床内颗粒速度、角度、接触数等颗粒运动形态的影响,揭示了柱状颗粒喷动行为的颗粒形状效应及微观机理。 提出了喷动床数值放大设计新方法。利用数值模拟技术实现了喷动床放大过程中气固流动行为的直观预测,获得了放大过程中关键参数随物料性质、床体结构和操作参数的变化规律,提出喷动床放大过程中关键参量预测关联式;利用模拟技术深入掌握喷动床关键部件形状、结构、尺寸改变对床内气固流动行为的影响规律;研发了工业尺度的喷动床混合器装置,完成了混合器详细尺寸设计和运行效果考察,给出混合器喷变工况运行特性以及操作运行指导,解决了15万吨/年非球生物质与类球热载体快速充分混合的实际工业需求。
英文题目 Investigations on flow characteristics and scaling of spouted bed with non-spherical particles
英文主题词 Spouted bed,non-spherical particle,scaleup/scale-up,CFD-DEM
英文摘要 Spouted bed, as one of the typical fluidization reactors, has been widely used in agriculture, food, pharmacy, energy, environment, chemical, nuclear technology and many other fields, with showing the commercial successes in a variety of physical operations such as drying, blending, granulation, cooling, coating, as well as the attractive prospect in the thermochemical processes including coal gasification, resourced utilization of biomass, oil shale pyrolysis, iron ore reduction, petroleum catalytic cracking, etc. Nevertheless, up to today, our knowledge on spouted bed is still very limited, especially in the aspects on the gas-solid dynamics of non-spherical particles and the scaleup, leading to numerous difficulties in scaling design and configuration optimization. The present work is devoted to revealing complex gas-solid flow characteristics and scaling relationships by experimental and simulated approaches. Spouted bed experimental system was established and the spouting behaviors of the mixtures of cylindroid particles and spherical bed materials were investigated. Results found in the spouted bed with two particles, the spouting and mixing usually synchronously develop, and when the spouting is well established, two particles in the bed are easy to achieve fulling mixing. The detailed relationships between spouting characteristics and the operating conditions were also obtained. Based on relationships, two different non-spherical particle spouting systems, i.e., the spouting system functioned by non-spherical particle and the spouting functioned by bed materials were proposed. The CFD-DEM modelling for spouting cylindroid particles was significantly improved in the current dissertation. The perfectly cylindroid particle was represented with the combined geometric elements method and by fully analyzing the various contact criterions between cylindroid surface, flats and edges and improving the syamlal-Obrien drag model, and thus calculating the contact forces between cylinders and interaction force between cylinders and gas more accurately, the CFD-DEM simulation on “turbulent gas phase + real cylinders + spouting” was first achieved. Based on the CFD-DEM simulations, the effects of particle shape on the spouting characteristics were investigated in the particle scale. The numerical scaleup and design method were developed. By directly predicting the gas-solid flow behaviors in large-scale spouted bed, the relationship between the minimum spouting velocity and the particle properties, bed structures and operating conditions were systematically studied and a new correlation was proposed. Lastly, the numerical scaleup and design method was used to design an industrial scale biomass-carrier mixer.
学术讨论
主办单位时间地点报告人报告主题
EFCE-Spain Group 2017 Barcelona 刘雪娇 CFD-DEM study on spouting behaviors with different particle shapes
蒙纳士大学 2016 墨尔本 刘雪娇 Mechanism and application of spouted beds with non-spherical particles
东南大学-蒙纳士大学 2014 苏州 刘雪娇 柱状与球形颗粒混合喷动特性研究进展
中国工程热物理学会 2015 南京 刘雪娇 过热蒸汽/热载体/生物质三相混合的数值模拟
东南大学 2014 南京 钟文琪 气固湍流多尺度机构演化与相互作用机理
东南大学 2014 南京 余艾冰 Particle scale study of particle and particle-fluid flows
东南大学 2013 南京 丁玉龙 纳米流体的流动与传热特性
东南大学 2015 南京 刘雪娇 数值模拟研究汇报
     
学术会议
会议名称时间地点本人报告本人报告题目
10th World Congress of Chemical Engineering 2017.10 Barcelona CFD-DEM study on spouting behaviors with different particle shapes
2015年中国工程热物理学会多相流学术年会 2015.11 南京 过热蒸汽/热载体/生物质三相混合的数值模拟
中澳颗粒技术研讨会 2014.12 苏州 柱状与球形颗粒混合喷动特性研究进展
62nd Canadian Chemical Engineering Conference 2012.10 Vancouver Evaluation on the effect of conical geometry on flow behaviors in spouted beds
     
代表作
论文名称
Prediction of minimum spouting velocity by CFD-TFM: Approach development
Evaluation on the effect of conical geometry on flow behaviors in spouted beds
Prediction of minimum spouting velocity of spouted beds by CFD-TFM: Scale-up
Mixing behaviors in an industrial-scale spout-fluid bed mixer by 3D CFD-DEM
Spouting behaviors of binary mixtures of cylindroid and spherical particles
 
答辩委员会组成信息
姓名职称导师类别工作单位是否主席备注
章名耀 正高 教授 博导 东南大学能源与环境学院
刘德彰 正高 教授 博导 南京航空航天大学能源与动力学院
卢平 正高 教授 博导 南京师范大学能源与机械工程学院 南京师范大学能源与机械工程学院院长
肖睿 正高 教授 博导 东南大学能源与环境学院 东南大学能源与环境学院院长
袁竹林 正高 教授 博导 东南大学能源与环境学院
      
答辩秘书信息
姓名职称工作单位备注
王沛 其他 讲师 东南大学能源与环境学院