基于图像信噪比的PSP图像平均幅数确定方法  

PSP Image Average Number Determination Method Based on Image Signal-to-Noise Ratio

作　　者：黄辉 熊健 刘祥 王红彪 HUANG Hui;XIONG Jian;LIU Xiang;WANG Hongbiao(China Aerodynamics Research and Development Center,Mianyang 621000,China)

机构地区：[1]中国空气动力研究与发展中心高速空气动力研究所,四川绵阳621000

出　　处：《计算机测量与控制》2023年第12期237-243,共7页Computer Measurement &Control

摘　　要：压敏漆测压技术具有非接触、全域测量的优点,广泛应用于模型表面压力分布测量;压敏漆试验中采用连续采集多幅图像求平均的方式降低图像噪声,一般根据经验确定图像采集幅数;对CCD相机的噪声类型进行分析,判断PSP测量系统随机噪声的主要来源为CCD光散粒噪声;提出了一种基于划分子区域的比图像信噪比计算方法,对比分析了某翼型和三角翼模型PSP试验数据不同图像平均幅数的处理结果,结果表明图像平均幅数增加到一定值后信噪比会趋于收敛,图像平均幅数减半后依然可以满足PSP测压试验精度要求,可通过分析信噪比确定每个工况采集的图像幅数,进而达到合理控制风洞试验时间的目的。Pressure sensitive paint measurement technology has the advantages of non-contact,full range measurement,it is widely used in the distribution measurement of model surface pressure.In pressure sensitive paint test,the continuous acquisition of multiple images and calculating the average image are used to reduce the noise,the number of the images is generally determined by experience.Scientific CCD camera's noise type is analyzed to judge that the main noise source of the pressure sensitive paint(PSP)measurement system is the CCD's optical scattering noise.A calculation method of image signal-to-noise ratio based on sub region is proposed,and the results of different average number of PSP test images of airfoil and delta wing model are compared and analyzed.The results show that the signal-to-noise ratio tends to converge when the average number of images is increased to a certain value,and the result can still meet the accuracy requirements of the PSP pressure test when the average number is halved.The required number of images could be determined by analyzing the signal-to-noise,which achieves the goal of reasonable control of wind tunnel test time,

关 键 词：压敏漆 电荷耦合器件 随机噪声 信噪比 图像平均幅数 

分 类 号：V211.74[航空宇航科学与技术—航空宇航推进理论与工程]