水滴撞击特性参数的动态图像测量方法

以染色法为基本原理,实验采集试件表面不同位置的染色过程视频.通过对视频数据的分析获取试件表面色度随时间增长的时序信号.实验过程可以划分为欠饱和区、平衡区和过饱和区.平衡区的比色值分布即为局部水收集系数分布的归一化结果.通过比色积分曲线的极限行为确定水滴撞击极限和总收集系数与最大局部水收集系数的比值.将实验结果与数值仿真结果和NASA(美国国家航空航天局)实验结果对比表明:水滴撞击特性参数与动态视频图像的RGB(rad-green-blue)色度空间可以建立较好的关联,实验重复性误差率小于±15%;水滴撞击特性参数之间存在内在关联.

Dynamic image processing measurement method of droplets impingement characteristics

Image processing method was applied to analyze the dying process at different locations on test cylinders in order to examine the variation of the surface chroma during the test.A complete test was divided into three stages:sub-dyed,balanced and over-dyed.The chroma distribution of balanced stage was normalized and defined as local water collection efficiency.Droplet impingement limits and the ratio of total impingement to the maximum local impingement efficiency can therefore be analyzed by the colorimetric integration curves.Comparing to the numerical simulation and the experiment of NASA (National Aeronautics and Space Administration),the current results indicate that water droplets impingement characteristics can be correlated with the dynamic RGB(rad-green-blue) color space,with ±15% repeatability error.Interrelation among the three characteristics was also observed.