Abstract: In order to study the characteristics of lean direct injection combustor with propane/air，two different kinds of axial swirlers and an injector for propane were designed. An experimental investigation was conducted to study the effects of swirler vane angles and injector depth on flow character and combustion performance with the single Lean Direct Injector (LDI) combustor，using propane as fuel . The results show that : (1)Swirler vane angle of 60° has larger total pressure loss and smaller effective area under the same inlet condition. (2)With the increase of the distance from the injector end planet to outlet of venturi，swirler vane angle of 45° has less total pressure loss and larger effective area，while the changes of swirler vane angle of 60° have no monotonicity，which mean the existence of best position for injector. (3) Outlet temperature of 45° swirler structure is higher than that of 60° swirler structure. (4) Equivalence ratio of ignition of swirler vane angle of 60° is lower than that of swirler vane angle of 45°. The equivalence ratio of 45° swirler is down to 0.7，while that of 60° swirler is as low as 0.6.

Key words: Low emission combustor；Lean direct injection；Swirler；Combustion characteristics

摘要： 为了研究丙烷/空气贫油直接喷射燃烧室的燃烧特性，设计了两种轴向旋流器和一种均布直射式丙烷喷注结构，建立了丙烷/空气贫油直接喷射燃烧平台，改变轴向旋流器叶片安装角和丙烷喷注结构位置，探讨轴向旋流器结构、旋流器和喷注结构匹配等因素对丙烷/空气贫油直接喷射燃烧特性影响及变化规律。研究结果表明:(1)60°叶片安装角旋流器结构，在相同进气条件下压力损失更大，有效面积更小；(2)随着丙烷喷注结构端面与文氏管出口距离的增加，45°安装角对应的旋流器结构的燃烧室总压损失减小，有效面积增加，而60°安装角对应的旋流器结构的燃烧室总压损失和有效面积均不呈现单调变化趋势，存在最优位置；(3)45°叶片安装角旋流器结构的燃烧温度高于60°叶片安装角旋流器结构；(4)相同条件下，60°叶片安装角旋流器结构的点火当量比低于45°叶片安装角旋流器结构，45°叶片安装角旋流器结构的点火当量比可达到0.7，60°结构所对应的最低当量比则为0.6。

关键词: 低排放燃烧室；贫油直接喷射；旋流器；燃烧特性