文档介绍：河北工业大学
硕士学位论文
液固循环流化床颗粒分布板的实验研究和数值模拟
姓名:林广周
申请学位级别:硕士
专业:化工过程机械
指导教师:张少峰
2011-05
河北工业大学硕士学位论文

液固循环流化床颗粒分布板的实验研究和数值模拟

摘要

在综合大量国内外文献基础上,设计出了一种曲面结构开孔分布板用来改善液固循环
流化床换热器内颗粒的分布不均匀情况,从而达到强化传热和防除垢的效果。
采用直径为 1 mm 刚玉球作为颗粒相,水为流动相,以三维 Navier-Stokes 方程作为
控制方程,结合两方程湍动模型,采用隐式有限体积法对床内的液固两相流动进行计
算。研究了液固流化床换热器下管箱安装分布板与否及分布板板面结构形式、液体流速、
初始固含率、安装高度比、分布板的大小对颗粒分布的影响,并通过下管箱内压力分布的
实验结果以及课题组先前的数据对所采用的数值计算方法进行了验证。通过对下管箱内流
动情况的模拟,得出了所设计的分布板对于颗粒分布的改善情况,并且得出了在安装该分
布板条件下较优的操作条件。
结果表明:在未安装分布板时颗粒在换热管内的分布非常不均匀,下管箱安装分布板
可以改善换热管束内颗粒分布的均匀性,且曲面分布板的改善效果优于平面分布板;分布
板安装高度比在 ~ 时,换热管束内颗粒分布均匀性较好;当分布板半径 R1 与入口
管径 R2 比为左右时,分布效果最为理想;在安装曲面分布板的情况下,换热管束内的
颗粒分布均匀性随着系统初始固含率及下管箱入口流速的增大而增强。压力实验结果和模
拟结果误差在 20%以内,验证了所选数学模型的准确性。

关键词:液固循环流化床,分布板,颗粒分布,不均匀度,数值模拟

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液固循环流化床颗粒分布板的实验研究和数值模拟

EXPERIMENTAL AND SIMULATIONAL RESEARCH
ON PARTICLES DISTRIBUTOR OF LIQUID-SOLID
FLUIDIZED BED

ABSTRACT

On the basis of investigation of plenty of literatures about the liquid-solid fluidized bed heat
exchanger, a new curve particles distributor was designed to improve the evenness.
Based on the 3D Navier-Stokes equations and two-equation  turbulence models ,
while particles (1mm in diameter) were as solid phase and water was as water phase, the
two-phase flow in liquid-solid fluidized bed heat exchanger was numerically simulated by
implicit finite volume methods. It studied how the distributor’s existence and structure, effects of
water velocity, types of distributor, presence of distributor, initial solids volume fraction, install
height ratio and the size of distributor’s effect on particles distribution. The simulation results
were verified by pressure distribution experiment of the lower vessel. After the simulation, a
better operating condition was gotten.
It shows that the existence of distributor improves the uniformity of the particles’
distribution in the heat