摘要
针对射流折射率场的非均匀分布会导致成像质量降低的问题,在真空实验舱内研究了不同总压条件下超声速半自由射流的光程差(OPD)分布。实验中三种光路的主光轴与流动方向夹角分别为81°、90°及99°。实验结果表明:总压越大,射流的OPD越大;相同总压条件下,81°光路的光程差大于99°光路和90°光路。推导了OPD沿流向分布的经验公式,并在此基础上分析了两种理论模型在该射流流场下的适用性。
Herein, the optical path difference(OPD) distribution of supersonic semi-free jet under different total pressure conditions was investigated in a vacuum chamber to address the problem of reduction of image quality attributed to the non-uniform distribution of jet refractive index field. The angle between the main optical axis of the three optical paths and the flow direction was 81°, 90°, and 99°. Experimental results show that larger total pressure corresponds to larger OPD of the jet. Under the same total pressures, the OPD of the 81° optical path is larger than the 99° and 90° optical paths. An empirical polynomial of the OPD along the flow direction was deduced, and the applicability of two theoretical models in the jet flow field was also analyzed.
作者
赵鑫海
易仕和
丁浩林
张锋
金龙
Zhao Xinhai;Yi Shihe;Ding Haolin;Zhang Feng;Jin Long(College of Aerospace Science cand Engineering,National University of De fense Technology,Changsha,Hunan 410073,China)
出处
《光学学报》
EI
CAS
CSCD
北大核心
2020年第7期1-5,共5页
Acta Optica Sinica
基金
国家自然科学基金(11172326,11302256)。
关键词
大气光学
超声速
半自由射流
光程差
观测角
atmospheric optics
supersonic
semi-free jet
optical path difference
looking angle
