基于EMMS曳力模型的循环流化床炉内双组份颗粒流动及燃烧数值模拟  

Numerical simulation of two-component particle flow and combustion in circulating fluidized bed furnace based on EMMS drag model

作　　者：麻芳娇 闫书凡 冯安稳 王孝强[1] 肖显斌[1,3] MA Fangjiao;YAN Shufan;FENG Anwen;WANG Xiaoqiang;XIAO Xianbin(School of New Energy,North China Electric Power University,Beijing 102208,China;Sany Renewable Energy Co.,Ltd.,Beijing 102206,China;Shanxi Research Institute of Huairou Laboratory,Taiyuan 030032,Shanxi China)

机构地区：[1]华北电力大学新能源学院,北京102208 [2]三一重能股份有限公司,北京102206 [3]怀柔实验室山西研究院,山西太原030032

出　　处：《电力科技与环保》2024年第6期591-602,共12页Electric Power Technology and Environmental Protection

基　　金：国家重点研发计划项目(2022YFB4100302)。

摘　　要：为解决传统单一粒径颗粒流化模型在反映循环流化床(circulating fluidized bed,CFB)锅炉实际运行状况上的不足,本文提出了一种适应宽筛分床料颗粒特性的数学模型,旨在提高CFB锅炉设计和运行优化的准确性。选取1台50 kW的CFB实验装置为研究对象,构建了基于能量最小多尺度(energy minimum multi-scale,EMMS)曳力模型的欧拉-欧拉双组份颗粒流动和燃烧的计算流体动力学模型,并对CFB炉内的流动及燃烧过程进行了三维数值模拟。模拟结果表明:双组份颗粒模型在温度分布和组分分布等关键参数的预测上与实验值的误差小于10%,显示出比传统单组份模型更高的吻合度。在双组份颗粒工况下,流动呈现典型的“环-核”模式,粗颗粒在提升管底部明显沉积,在距离一次风口约0.2 m处达到堆积峰值。在密相区,双组份模型预测的温度略高于单组份模型;且SO_(2)和NO浓度显著受到二次风的影响。此模型能够更准确地反映CFB炉内部的燃烧与流动过程,为CFB锅炉的流态优化研究和工程应用提供了重要的参考依据。In order to solve the limitations of traditional single-particle size fluidization models in reflecting the actual operational conditions of circulating fluidized bed(CFB)boilers,a mathematical model tailored to the wide particle size distribution characteristics of bed materials was proposed.It aimed at enhancing the accuracy of CFB boiler design and operational optimization.A 50 kW CFB experimental experimental device was selected as the research subject,for which an Euler-Euler two-component particle phase flow and combustion computational fluid dynamics model based on the energy minimization multi-scale(EMMS)drag model was developed,and a three-dimensional numerical simulation of the flow and combustion processes within the CFB boiler was conducted.The numerical simulation results demonstrated that the two-component particle model predicted temperature distribution and composition distribution with an error of less than 10%compared to experimental data.A higher degree of accuracy than the traditional singlecomponent particle model was showed.Under the two-component particle condition,the flow exhibited a typical"coreannulus"pattern,with coarse particles prominently settling at the bottom of the riser,peaking at about 0.2 m from the primary air inlet.In the dense phase region,the temperatures predicted by the two-component particle model were slightly higher than those of the single-component particle model.Additionally,the concentrations of SO2 and NO were significantly influenced by the secondary air.This model more accurately reflects the combustion and flow processes inside the CFB boiler,providing a vital reference for the optimization of CFB boiler operations and engineering applications.

关 键 词：EMMS曳力模型 双组份颗粒 循环流化床 数值模拟 

分 类 号：TK16[动力工程及工程热物理—热能工程]