基于光场成像的燃烧颗粒粒径与速度测量方法

为实现固体推进剂中金属燃料动态燃烧的精细化表征，提出一种基于光场成像的固体推进剂中燃烧颗粒粒径与速度三维动态同步测量方法。构建固体推进剂燃烧光场成像测量系统，获得金属颗粒动态燃烧过程的光场图像，通过重聚焦算法得到燃烧颗粒场的重聚焦图像；进一步开展光场相机标定实验，获取深度与最佳重聚焦参数的关系曲线；利用图像分割算法对重聚焦图像中的颗粒进行识别和定位，获取燃烧颗粒的粒径大小，并结合三维粒子跟踪技术对颗粒的轨迹和速度进行重构；开展推进剂药条燃烧实验验证研究。结果表明：光场成像技术能够获得不同深度的颗粒信息，跟踪颗粒的动态燃烧过程，并实现对燃烧金属颗粒粒径与三维速度的同步测量。

Simultaneous measurement of size and velocity of burning particles based on light field imaging

To characterize the dynamic combustion behavior of metal fuel in solid propellants, a simultaneous measurement method for the burning particle size and velocity based on light field imaging is proposed in this paper. A light field imaging system is established and the burning metal particles are imaged by the light field imaging system. The refocusing images of the burning particles are further obtained through refocusing algorithm. The calibrations of the light field system are carried out and the relationship curve between the depth and the optimal refocusing parameter is determined. The image segmentation algorithm is used to identify and locate the particles in the refocused image and then the particle sizes of the burning particles are calculated. Following the identification and localization of the particles in the refocused image using the image segmentation technique, the burning particle sizes are determined. The trajectories and velocities of particles are reconstructed through 3D particle tracking technology. Experimental results illustrated that the light field imaging technology is capable of making 3D measurements of the size and velocity of the burning particles of metal fuel, and characterizing the combustion process of metal particles. The results of the experiments showed that the light field imaging technique is able to characterize the combustion process of metal particles and make 3D measurements of the size and velocity of the burning metal fuel particles.