掺混孔结构对大曲率受限空间出口温度分布的影响

Effects of Dilution Hole Structure on Exit Temperature Distribution Characteristic in Large Curvature Limited Space

回流燃烧室的掺混射流在大曲率受限的弯管中与主流掺混,回流导致沿径向的压力梯度变化,增加了掺混流动的复杂性。为了研究不同掺混孔结构对掺混射流与主流在大曲率弯曲通道内的掺混规律,在有收缩比弯曲通道中多孔射流的出口温度分布测试中,对影响掺混冷却的各变化参数按照单一变量进行比对研究,对孔径、孔间距等掺混孔结构变量弯曲通道内的掺混效果进行分析,选择一种结构在三头部回流燃烧室进行了出口温度场的分布初步验证,得到了比较均匀的燃烧室出口温度分布,所得的规律可以作为回流燃烧室的掺混结构设计和优化的参考依据。

The dilution jet in small reverse flow combustor is mixing with the main flow in a large curvature limited space. The gas flow accelerates and flow direction turns sharply which results in complicated flow condition by a variation of radial pressure gradient. In order to study effects of structure of the dilution hole on transverse jet mixing,the exit temperature distribution of multiple jets in large curvature limited space has been studied. The parameters of diameter of dilution hole,spacing between jets have been analyzed and summarized for the design experience. At last one of the dilution hole structure has been validated in a three injector reverse flow combustor,the preliminary results show that a relatively uniform exit temperature distribution of the combustor was achieved. The qualitative results of the dilution hole structure effect on the mixing could be a reference for the reverse flow combustor design and optimization.