多级调风预燃式旋流燃烧器冷态试验研究  

Cold experiment research of multi-stage air-regulating pre-combustion cyclone burner

作　　者：牛艳青[1] 薛旭峰 张浩 惠世恩[1] NIU Yanqing;XUE Xufeng;ZHANG Hao;HUI Shien(School of Energy and Power Engineering,Xi′an Jiaotong University,Xi′an710049,China)

机构地区：[1]西安交通大学能源与动力工程学院,陕西西安710049

出　　处：《洁净煤技术》2021年第5期196-203,共8页Clean Coal Technology

基　　金：国家自然科学基金面上资助项目(51776161)。

摘　　要：煤粉预热低氮燃烧技术是燃烧技术领域的研究重点。为了响应“节能环保、绿色低碳经济”的时代发展要求,针对煤炭燃烧过程中产生大量污染物如NO_(x)、SO_(x)等环境问题,基于前人研究结果,设计开发了一种多级调风预燃式旋流燃烧器。耦合预燃室煤粉预热燃烧技术与空气分级燃烧技术,生成高还原性氛围回流区,在有效控制NO_(x)生成的同时,提升难燃煤种着火性能。主要通过冷态模型试验,研究了不同配风比对多级调风预燃式旋流燃烧器空气动力场的影响,利用新型三孔探针测速方法进行了流场测试与分析。结果表明:在总风量一定的情况下,一次风率、旋流内二次风率及外二次风率分别为20.8%、37.5%和31.2%时,回流区长度、宽度、面积和回流率达到最大值,回流效果最好,有利于煤粉着火与低NO_(x)燃烧。预燃室的存在有利于形成煤粉稳定燃烧的回流区,其中旋流内二次风是影响回流区气流特性的主要因素,主导形成预燃室内的中心回流区;外二次风通过卷吸炉膛内的气流影响预燃室回流区温度,是预燃室内外围回流区生成的根本原因;具有一定刚性的一次风和直流内二次风会压缩回流区,影响燃烧器的稳燃效果。Pulverized coal preheating low-nitrogen combustion technology is the research focus of combustion technology.In order to respond to the era development requirements of"energy saving,environmental protection,green and low-carbon economy",and solve the environmental problems of a large number of pollutants produced during the combustion process of coal such as nitrogen oxides and sulfur oxides,a multi-stage air-regulated pre-combustion swirl burner was designed and developed on the basis of a large number of previous studies on preheating combustion technology.The pre-combustion chamber pulverized coal preheating combustion technology is coupled with the air staged combustion technology to generate a highly reducing atmosphere recirculation zone,effectively controlling the generation of NO_(x),and improving the ignition performance of refractory coals.In this paper,the influence of different air distribution ratios on the aerodynamic field of the multi-stage air-regulated pre-combustion swirl burner was mainly studied through the cold state model test,and the flow field was tested and analyzed by using the new three-hole probe velocity measurement method to carry out.The results show that under the condition of the constant total air volume,when the primary air rate,the swirl internal secondary air rate and the external secondary air rate are 20.8%,37.5%and 31.2%,the length,width,area and return flow of the recirculation zone reach the maximum,and the the reflux effect is the best,which is conducive to pulverized coal ignition and low NO_(x) combustion.The existence of the pre-combustion chamber is conducive to the formation of a recirculation zone for stable combustion of pulverized coal,and the swirl internal secondary air is the main factor that affects the airflow characteristics of the recirculation zone,which dominates the formation of the central recirculation zone in the precombustion chamber.The external secondary air affects the temperature of the recirculation zone of the precombustion chamber through th

关 键 词：旋流燃烧器 预燃室 多级配风 回流区 低NO_(x)燃烧 

分 类 号：TK223.2[动力工程及工程热物理—动力机械及工程]