超高速碰撞碎片云的激光阴影照相技术

为研究超高速碰撞过程中所产生碎片云的特性，在中国空气动力研究与发展中心超高速碰撞靶上建立了激光阴影照相系统。该系统由YAG激光光源、阴影仪和成像系统组成，在采用补偿式滤光等技术后，获得了撞击速度v≈6km／s时清晰的碎片云图像。本文对该系统的工作原理、系统构成以及调试情况进行了介绍。试验结果表明：(1)该系统可以获得清晰的超高速碰撞碎片云图像；(2)扩束镜、成像物镜质量本身是影响碎片云激光阴影成像质量的主要因素；(3)各光学元件的不同结构及不同放置也会严重影响阴影成像质量。

Laser shadowgraph for the visualization of hypervelocity impact debris cloud

To visualize the hypervelocity impact debris cloud a laser shadowgraph system has been set up on the hypervelocity impact range of Hypervelocity Aerodynamics Institute, CARDC. The system includes YAG laser source, shadowgrapher and imaging system. Satisfying debris cloud image, with impact velocities up to 6km/s, was obtained with the compensated filter adopted. Introduced in this paper are the principle, structure and the debug of the system. The test results showed that: (1) satisfying debris cloud image could be obtained with this system, (2) beam expander and imaging lens are the main factors which would influence the quality of image, (3) the structure and position of each optical element would also affect the image quality.