Study on Combustion Performance of the Radial Staged Combustion Chamber with Lobed Nozzles

波瓣喷嘴径向分级燃烧室的燃烧性能研究

In order to investigate the effect of the radial gradation of the lobed nozzles on the flow field organization,a cold water model experimental platform for a combustion chamber with radial⁃staged 13-point lobed nozzles is built.Compared with a series of combustion OH*luminescence experiments tested by the University of Cincinnati,the four corresponding working conditions of no load,partial load,cruise and take off are selected.The vortex structure,vorticity value,multi-combustion materiel field and combustion characteristics of the flow field in the radial staged combustion chamber of the lobed nozzles under the equivalence ratio,the fuel injection method,the fuel injection ratio and other factors are numerically studied.The results show that under different influencing factors,the varation trend of the hydroxyl flame field of the lobe combustion chamber is basically the same as that of the hydroxyl light emission experiment of the swirl combustion chamber,but the flame field shape is quite different.The local equivalent ratio has a greater influence on the relevant combustion performance of the combustion chamber.Under the conditions of lower equivalence ratio,three-stage air and fuel injection mode,and gradually transferring the fuel flow of the pilot circuit to the external circuit,the temperature field and flame field of the combustion chamber are more evenly distributed,the outlet temperature field quality is better,the combustion efficiency is higher,and the NO_(X) emission is relatively low.These are basically consistent with the cold test results.The cold experimental results illustrate the importance of the influence of the flow field organization on the combustion organization and verify the reliability of the calculation results.

为了探究波瓣喷嘴径向分级方式对流场组织方式的影响,搭建了13点波瓣喷嘴径向分级燃烧室冷态水模实验台。对比辛辛那提大学测试的一系列燃烧羟基发光实验,选取空载、部分载荷、巡航和起飞4种对应的工况,对当量比、燃料喷射方式和燃料喷射比例等因素下波瓣喷嘴径向分级燃烧室内的流场涡系结构、涡量值、燃烧多物量场以及燃烧特性,进行了数值研究。结果表明:在不同影响因素下,波瓣燃烧室的羟基火焰场变化规律与旋流燃烧室羟基发光实验变化规律基本相同,但其火焰场形状存在较大差别。局部当量比对燃烧室的相关燃烧性能影响较大。较低当量比、3级空气和燃料喷射方式以及将先导回路燃料流逐渐转移到外部回路的条件下,燃烧室的温场、火焰场分布比较均匀,出口温度场品质较好,燃烧效率较高,NO_(X)排放量比较低,与冷态实验结果基本符合。冷态实验结果说明了流场组织方式对燃烧组织方式影响的重要性,同时也验证了计算结果的可靠性。