火焰筒扩张角与旋流匹配对燃烧特性的影响

为研究旋流器流量分配对干式低排放(Dry Low Emission，DLE)燃烧室燃烧特性的影响规律，针对单头部中心分级旋流燃烧室，以天然气作为燃料，在保持旋流数不变的前提下开展两级旋流器不同空气分配比例下的试验测试和数值模拟，获得不同结构参数条件下燃烧室的综合燃烧性能以及污染物排放等变化规律。研究表明：随主燃级/预燃级旋流器流量比增大，燃烧室中心回流区变小、回流区长度变短；预燃级局部当量比的增大造成燃烧室出口CO排放增加，主燃区燃烧加剧，热力型NOx排放也增加；同时，燃烧室中心高温区域向燃烧室出口方向扩张，出口温度分布均匀性变差。

Influence of flame tube expansion angle and swirl matching on combustion

To investigate the effect of swirling flow distribution on the combustion characteristics of dry low emission (DLE) combustion chamber, on the premise of unchanged swirl number, experimental tests and numerical simulations were carried out for two stage swirler in a single dome center staged swirl combustion chamber by using natural gas as fuel at different air flow split ratios. The change rules of integrated combustion performance and pollutant emission of the combustion chamber under different structural parameters were obtained. Research shows that with the increase of flow ratio of primary combustion stage/pre combustion stage swirlers, the area and length of recirculation zone at the center of the combustion chamber becomes smaller and shorter; the increase of local equivalence ratio at the pre combustion stage results in an increase of CO emission at the outlet of combustion chamber, and thermal NOx emission also increases as primary combustion stage burns severely; meanwhile, the high temperature area expands towards the outlet of the combustion chamber, which deteriorates the outlet temperature distribution uniformity.