摘要
温度场作为一种状态监测参数,在大型工业装备状态监测领域有着广泛应用,纹影法作为一种流场可视化方法,是进行空间温度场测量的有效手段。传统纹影法一般通过直接测量光线偏折角重构空间折射率场,进而解算温度场,然而光线偏折角一般非常微小,直接测量会产生较大的测量误差。因此,本文提出一种采用干涉条纹的纹影偏折角放大方法,从而提高空间温度场重构精度。首先,测量激光通过双缝后将形成干涉条纹以代替传统背景纹影法的随机散斑图案;接着,通过视觉的方法测量干涉条纹穿越非均匀温度空间后所产生的条纹偏移,并基于该偏移量解算光线偏折角;然后,通过阿贝尔逆变换的方法解算空间折射率场的分布情况,进而获取空间温度场,最后,通过仿真与实验对本文所提方法的有效性及测量精度进而了验证。实验结果表明:与传统的背景纹影法相比,温度场重构误差下降约30%。本文所提的干涉条纹纹影法可有效提高纹影测量精度,拓展纹影温度测量的应用范围。
The temperature field is a common condition-monitoring parameter that is widely used to monitor the condition of large industrial equipment. The schlieren method is an effective flow-field visualization method to measure the spatial temperature field. The traditional schlieren method rebuilds the spatial refractive index field by directly measuring the light deflection angle and then calculating the temperature field. However, the light deflection angle is generally very small, and direct measurements produce large measurement errors. A method that uses interference fringes to amplify the light deflection angle is proposed, effectively improving the measurement accuracy of the schlieren technique. First, interference fringes were formed using a measuring laser that passes through a double slit to replace the random speckle pattern of the traditional schlieren method. When the fringe generated by interference fringes crosses the nonuniform temperature space, the fringe offset was measured by visual measurement, and the light deflection angle was calculated based on the offset. Next, the distribution of the spatial refractive index field was calculated using the Abel inverse transformation method to obtain the spatial temperature field. Finally, the effectiveness and measurement accuracy of the proposed method were verified experimentally using simulation. The experimental results showed that the temperature field reconstruction error induced in our method decreased by approximately 30% compared with the error induced in the traditional schlieren method. The proposed interference fringe schlieren method effectively improves the accuracy of schlieren measurement and expands the application range of schlieren temperature measurement.
作者
吴军
宋丰成
潘智祥
张琛萍
郭润夏
张晓瑜
WU Jun;SONG Fengcheng;PAN Zhixiang;ZHANG Chenping;GUO Runxia;ZHANG Xiaoyu(College of Aeronautical Engineering,Civil Aviation University of China,Tianjin 300300,China;College of Electronic Information and Automation,Civil Aviation University of China,Tianjin 300300,China)
出处
《光学精密工程》
EI
CAS
CSCD
北大核心
2023年第2期150-159,共10页
Optics and Precision Engineering
基金
国家自然科学基金资助项目(No.52005500,No.62173331)
天津市教委科研计划资助项目(No.2020KJ013)。
关键词
纹影法
轴对称温度场
干涉条纹
激光诊断
schlieren method
axisymmetric temperature field
interference fringe
laser-diagnose technology
