可调轴向叶片结构旋流强度计算与动力场特性分析  

Calculation of structural swirl intensity and analysis of dynamic field characteristics of adjustable axial blades

作　　者：王学文 崔豫泓 WANG Xuewen;CUI Yuhong(China Coal Research Institute Company of Energy Conservation,Beijing 100013,China;State Key Laboratory of High-efficiency Mining and Clean Utilization of Coal Resources,Beijing 100013,China;National Key Laboratory of Efficient Utilization of Energy and Energy and Emission Reduction Technology,Beijing 100013,China)

机构地区：[1]煤科院节能技术有限公司,北京100013 [2]煤炭资源高效开采与洁净利用国家重点试验室,北京100013 [3]国家能源煤炭高效利用与节能减排技术装备重点试验室,北京100013

出　　处：《煤质技术》2021年第5期31-36,共6页Coal Quality Technology

基　　金：煤科院节能技术有限公司科技发展基金资助项目(2020JNCX01-05)、(2020JNZD-01)。

摘　　要：旋转射流对燃烧器的燃烧过程起着重要的作用,可调轴向叶片旋流器是实现旋转射流的重要途径。为了充分发挥可调轴向叶片旋流器的结构简单、阻力损失小、出口速度分布均匀以及调节性较好等优势,基于可调轴向叶片旋流器的工作原理,研究不同旋流强度下燃烧室内轴向速度、切向速度、径向速度的径向分布以及煤粉火焰温度的轴向与径向分布,对系统改变旋流器位置后可调轴向叶片旋流器的动力场特性进行分析,确定旋流器的结构参数并推导可调轴向叶片旋流器旋流强度的计算公式。研究结果表明:调节旋流器位置可改变气流轴向动能和切向动能的大小,导致旋流器出口附近轴线逆压梯度区的建立,使得气流反转以影响流场;随着旋流强度的增大,中心回流区面积增加,烟气温度峰值首先出现在燃烧器喷口附近,整个回流区内平均温度较高且比较均一,说明提高旋流强度有助于燃烧器内煤粉的稳定着火。The rotating jet plays an important role in the combustion process of the combustor,and the adjustable axial vane swirler is an important way to realize the rotating jet.In order to develop the advantages of adjustable axial vane hydrocyclone,such as simple structure,small resistance loss,uniform outlet velocity distribution and the better adjustability,based on the working principle of adjustable axial vane hydrocyclone,the radial distributions of axial velocity,tangential velocity and radial velocity in combustion chamber,the axial and radial distributions of pulverized coal flame temperature under different swirl intensity were studied.The dynamic field characteristics of the adjustable axial vane hydrocyclone after the system changes the position of the hydrocyclone were analyzed,the structural parameters of hydrocyclone were determined,and the formula for calculating the swirl intensity of the adjustable axial vane swirler was derived and proposed.The results show that:adjusting the position of the cyclone can change the axial kinetic energy and tangential kinetic energy of the air flow,leading to the establishment of the axial reverse pressure gradient zone near the outlet of the cyclone,making the airflow reverse to affect the flow field;as the swirling intensity increases,the area of the central return zone increases,the flue gas temperature peak first appeared near the burner nozzle,and the average temperature in the entire recirculation zone was relatively high and relatively uniform,indicating that increasing the swirling intensity would help to stabilize the pulverized coal ignition in the burner.

关 键 词：旋转射流 可调轴向叶片 动力场特性 结构旋流强度 计算公式 径向分布 中心回流区 烟气温度峰值 

分 类 号：TK223.23[动力工程及工程热物理—动力机械及工程]