High frequency Rayleigh scattering measurements of density fluctuations in high-pressure premixed combustion
High frequency Rayleigh scattering measurements of density fluctuations in high-pressure premixed combustion
复制标题
高压预混燃烧中密度波动的高频瑞利散射测量
DOI：
10.1063/5.0102330
复制
发表时间：
2022
期刊：
影响因子：
--
通讯作者：
W. Hwang
中科院分区：
文献类型：
--
作者：
H. Park;Sangeun Bae;H. Do;W. Hwang
在高温高压环境中以高频测量物理流动特性（如密度和温度）是非常具有挑战性的。这些特性的快速波动通常会影响燃烧效率和稳定性。在此，我们尝试使用高时间分辨率的激光瑞利散射测量在高压预混燃烧的密度波动。由于信噪比较低，因此通过计数单个光子来评估Rayleigh散射强度。测量系统首先在各种空气压力下进行了验证，没有燃烧。然后在从1巴到7巴的四种不同压力下进行燃烧实验。密度波动随压力增大而增大，但主波动频率减小。用本征正交分解（POD）分析火焰阵面的高速纹影图像来验证结果。
Measuring physical flow properties such as density and temperature at high frequency in high temperature and pressure environments is very challenging. Rapid fluctuations of these properties often have an impact on combustion efficiency and stability. We hereby attempt to measure density fluctuations in high-pressure premixed combustion using high temporal resolution laser Rayleigh scattering. The Rayleigh scattering intensity was assessed by counting individual photons due to the low signal to noise ratio. The measurement system was first verified at various air pressures without combustion. Combustion experiments were then conducted at four different pressures, from 1 to 7 bar. The density fluctuations increased with pressure, but the dominant fluctuation frequency decreased. Proper orthogonal decomposition (POD) analysis of high-speed Schlieren images of the flame front was used to verify the results.