旋流燃烧器的结构参数会对航空发动机燃烧室的燃烧过程产生影响，为了获取高分辨率的流场三维信息以分析旋流燃烧器对燃烧室燃烧性能的影响并提出优化策略，可通过背景导向纹影层析（BOST）技术实现复杂流动的三维折射率、密度和温度分布的瞬态重建。首先采用镜头等效光学系统和龙格-库塔光线追迹方法对光线偏折产生的畸变图像进行模拟，在此基础上采用光流方程重建模型对规则和复杂对象的折射率场进行了重建模拟，分析了图像偏移大小的影响因素，计算了测量体、焦距等设置参数对重建误差的影响，提出了背景导向纹影的优化测量设置方法。模拟结果显示采用优化设置参数后重建折射率场较好地展示了湍流旋流火焰的旋进射流、褶皱和涡旋等流场复杂结构。

The structural parameters of the swirl combustors will affect the combustion process of the aeroengine combustion chamber. In order to obtain high-resolution three-dimensional flow field information， analyze the influence of the swirl combustors on the combustion performance of the combustion chamber and subsequently put forward optimization strategies， the Background Oriented Schlieren Tomography technique （BOST） can be used to reconstruct the instantaneous three-dimensional refractive index， density and temperature distribution of complex flows. First， the lens equivalent optical system and Runge-Kutta ray tracing method are used to simulate the distorted image caused by ray deflection. On this basis， the refractive index field of regular and complex objects is reconstructed using the optical flow equation reconstruction model. The influencing factors of image distortion are analyzed. The influence of measurement volume， focal length and other setting parameters on the reconstruction error is calculated. The optimized measurement setting method of background oriented schlieren is proposed. The simulation results show that the reconstructed refractive index field with optimized parameters show the complex flow field structures such as swirling jet， fold and vortex of turbulent swirling flame.