斜壁限制域台阶对火焰宏观结构的影响  

Influence of slope-wall confinement step on flame macrostructure

作　　者：覃子宇 韩啸[1] 李磊[1] 林宇震[1] 王思睿 徐亮亮 QIN Ziyu;HAN Xiao;LI Lei;LIN Yuzhen;WANG Sirui;XU Liangliang(Research Institute of Aero-Engine,Beihang University,Beijing 100191,China;School of Mechanical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]北京航空航天大学航空发动机研究院,北京100191 [2]上海交通大学机械与动力工程学院,上海200240

出　　处：《航空动力学报》2025年第2期405-413,共9页Journal of Aerospace Power

基　　金：国家自然科学基金(52106128);航空发动机及燃气轮机基础科学中心项目(P2022-A-Ⅱ-006-001);中央高校基本科研业务费专项资金。

摘　　要：斜壁限制域是一种有效的燃烧振荡被动控制方法。为深入认识其火焰稳定特性,探究斜壁限制域台阶高度对火焰宏观结构的影响规律。数值仿真表明增大台阶高度使火焰宏观结构从V型转变为M型。通过定量计算火焰拉伸率,发现这一转变伴随着斜壁过渡段外侧出现明显的强拉伸流动区域。结合小扰动线性稳定性理论对该现象加以解释,其原因可总结为结构特征尺度大于空间不稳定模态1/4波长尺度,进而固有的不稳定模态被激发,并形成稳定火焰的强拉伸区。运用该方法预测临界台阶高度,绝对误差不超过0.1 mm。Slope-wall confinement is an effective passive control method for combustion oscillation.To deeply understand its flame stabilization characteristics,the influence of step height in the slope-wall confinement on the flame macrostructure was explored.Numerical simulation showed that increasing the height of the step changed the flame macrostructure from V-shaped to M-shaped structure.By quantitatively calculating the flame stretch rate,it was found that this transition was accompanied by the occurrence of an area with a significantly strong stretch flow on the outside of the slope-wall transition section.Combined with the small disturbance linear stability theory,the reason for this phenomenon can be summarized as the structural feature-length scale was larger than the spatial unstable mode 1/4 wavelength length scale.Thus,the inherently unstable mode was excited,and a region with a strong stretch rate for flame stabilization was formed.This method was used to predict the height of the critical step,through which the absolute error did not exceed 0.1 mm.

关 键 词：斜壁限制域 火焰宏观结构 火焰拉伸率 线性稳定性分析 空间模态 

分 类 号：V231.2[航空宇航科学与技术—航空宇航推进理论与工程]