Hydrodynamic Analysis on a Slurry Bubble Column Using Ultrasonic Technique

使用超声波技术对浆液气泡塔进行水动力分析

• 批准号: 07650890
• 负责人: UCHIDA Shigeo
• 金额: $ 1.34万
• 依托单位: Shizuoka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07650890/
• 关键词: Slurry Bubble Column; Ultrasonic; Holdup; flow scheme; Transmission time; 伝播時間

In this work, an ultrasonic method has been developed to analyze the hydrodynamics in a slurry bubble column. To establish the ultrasonic technique, the relationships among velocity difference in term of transmission time difference of ultrasound, the ultrasonic attenuation and the dispersed phase holdups in gas-liquid and liquid-solid systems have been derived. Comparison between the theory and the experimental results showed a good agreement. Based on those relations, a model for simultaneous measurement of gas and solid holdups in three-phase systems has been proposed by utilizing the velocity changes of two ultrasonic pulses with different frequencies or the velocity change and the attenuation of one ultrasonic pulse.The method gas been applied to investigate the axial as well as radial distributions of gas and solid holdups in a slurry bubble column for various operating variables. The macroscopic flow scheme model in the slurry bubble column has been proposed based on the structu … More re of the bubble distribution. The relationships among the gas bubble distribution, the flow scheme and the particle concentration distribution have been investigated for various operating variables including the gas and the liquid velocities, the amount of solid loading and particle diameter. The mechanism of radial migration of solid particles in the slurry bubble column has been discussed.To describe the radial distribution of the gas bubble and the solid particles in the slurry bubble column, a bubble-wake-particle diffusion model has been proposed. The model has been developed by combining the bubble-wake model and the particle/bubble diffusion model and by taking into account of the bubble-particles and wake-particles interactions, the particles diffusion and the lateral lift force. The calculated particles distribution profiles have been aompared with the measured ones by the ultrasonic method, and showed that the model can describe well the trend of the distributions observed experimentally. Less

在本工作中，建立了一种超声方法来分析浆液泡塔的流体力学。为了建立超声技术，推导了超声在气液和液固两种体系中的传播时间差、超声衰减与弥散相占率之间的关系。理论与实验结果比较，结果吻合较好。在此基础上，提出了利用两个不同频率超声脉冲的速度变化或一个超声脉冲的速度变化和衰减量同时测量三相系统气固含率的模型。本文应用该方法研究了不同操作变量下浆态泡塔内气体和固体含率的轴向和径向分布。提出了基于结构的浆体气泡柱宏观流动方案模型，并对气泡分布进行了进一步研究。研究了在气液速度、固载量和颗粒直径等操作变量下气泡分布、流动方式和颗粒浓度分布之间的关系。讨论了浆料泡塔内固体颗粒径向迁移的机理。为了描述浆液泡柱中气泡和固体颗粒的径向分布，提出了气泡-尾迹-颗粒扩散模型。该模型将气泡-尾流模型与颗粒/气泡扩散模型相结合，考虑了气泡-颗粒和尾流-颗粒的相互作用、颗粒的扩散和侧向升力。将计算得到的颗粒分布曲线与超声测量得到的颗粒分布曲线进行了比较，结果表明该模型能较好地描述实验观测到的颗粒分布趋势。少

项目成果

Warsito: "Distributions of Gas and Sold Holdups in Slurry Bubble Column Measured by Ultrasonic Method" Proc of the 5th World Congress of Chem. Eng.271-276 (1996)

Warsito：“超声波法测量的浆液气泡塔中的气体分布和滞留量”第五届世界化学大会论文集。

Warsito et al.: "Bubble-wake and Particle Diffusion Model to Predict the Radial Solid Concentration Profiles in Three-Phase Fluidized Bed" Proc.of ASCONFBR '96, Histou, Taiwan. 340-345 (1996)

Warsito 等人：“预测三相流化床径向固体浓度分布的气泡尾流和粒子扩散模型”Proc.of ASCONFBR 96，Histou，台湾。

ワルシト: "超音波による二種類の粒子を用いた懸濁気泡塔内の各相ホールドアップの測定" 化学工学シンポジウムシリーズ. 50. 120-125 (1996)

Warsito：“使用超声波测量悬浮气泡塔中各相的滞留量”化学工程研讨会系列 50. 120-125 (1996)。

Warsito et al.: "Distributions of Gas and Solid Holdups in Slurry Bubble Column Measured by Ultrasonic Method" Proc.of the 5th World Congress of Chem.Eng, San Diego, US. 271-276 (1996)

Warsito 等人：“用超声波方法测量的浆液气泡塔中气体和固体含率的分布”，第五届世界化学工程大会论文集，美国圣地亚哥。

Warsito: "Bubble-wake and Particle Diffusion Model to Predict the Radial Solid Concentration Profiles in Three-Phose Fluidized Bed" Proc. of ASCON FBR '96. 340-345 (1996)

Warsito：“用于预测三相流化床径向固体浓度分布的气泡尾流和粒子扩散模型”Proc。