电站锅炉双可调煤粉分配器气固两相流动特性研究  

Research on Gas-Solid Two-phase Flow Characteristics of Double-adjustable Pulverized Coal Distributors in Power Station Boilers

作　　者：薛飞宇 韩健民 梁双印[1] XUE Feiyu;HAN Jianmin;LIANG Shuangyin(School of Energy,Power and Mechanical Engineering,North China Electric Power University,Beijing 102206,China)

机构地区：[1]华北电力大学能源动力与机械工程学院,北京102206

出　　处：《动力工程学报》2021年第12期1033-1039,1108,共8页Journal of Chinese Society of Power Engineering

基　　金：中央高校基本科研业务费专项资金资助项目(2019JG004)。

摘　　要：针对制粉系统一次风粉的流动均匀性会直接影响锅炉的安全性与经济性,提出了一种双可调煤粉分配器。利用环形渐缩阀将风粉两相流分离为浓相流和稀相流,使用开度可调的扇形阀分别调整风粉流量,最后将浓、稀两股流体混合均匀,同时计算了内部结构对煤粉分配器进出口压降分配效果的影响。结果表明:渐缩角度范围取65°~75°较合适,高度占比不宜超过60%;风粉分离过程对粒径大于等于50μm的煤粉颗粒具有较好的分离效果;稀相扇形阀对单支管最大出口风速偏差为-28.63%,浓相扇形阀对单支管最大出口粉量偏差为-32.61%;该分配器对风粉调控具有较好的独立性,可以显著提高风粉系统流动的均匀性和调节灵活性。Considering the effects of the flow uniformity of the primary air and powder in the pulverizing system directly on the safety and economy of the boiler,a double adjustable pulverized coal distributor was proposed.Tapered valves were used to separate the two-phase flow of air and powder into a dense and dilute phase flow,a fan valve with an adjustable opening was used to adjust the flow respectively.Finally,the thick and thin fluids were mixed evenly,and the influence of the internal structure on the distribution of the outlet pressure drop of the distributor was calculated.Results show that the suitable range of annular taper angle is 65°-75°,and the height proportion should not exceed 60%.The air-powder separation process has a good separation effect on coal particles with particle size larger than 50μm.The deviation of the dilute phase flow valve on the maximum outlet wind speed of a single pipe is-28.63%,which of the dense phase flow valve on the maximum powder volume is-32.61%.The distributor has great independence in controlling the wind and powder,which can significantly improve the uniformity and adjustment flexibility of the air powder system.

关 键 词：煤粉分配器 分离性能 流场特性 偏差调节 数值模拟 

分 类 号：TK229[动力工程及工程热物理—动力机械及工程]