激光驱动飞片的线面成像VISAR测速技术

以激光驱动飞片速度场诊断为例,展示线面同时成像任意反射面速度干涉仪(VISAR)技术在超高速碰撞研究中的应用前景。将传统VISAR改为成像干涉结构,用变像管扫描相机和高速光电分幅相机分别记录作为信号载体的梳状干涉条纹随时间的变化,实现靶面一条线上各点速度历程和多个时刻二维靶面上所有点速度相对分布的测量。所研制的线面同时成像VISAR具有10μm的空间分辨和约15m/s的速度分辨能力。用其测量了激光驱动铝膜飞片的速度场,直观给出飞片的演化发展过程。实验结果表明,线面同时成像VISAR技术可以为激光驱动飞片、超高速碰撞等领域的理论研究和数值模拟提供有效比对实验数据。

Line-imaging and framing plane-imaging velocity interferometer for laser driven flyer diagnostics

A potential of line and plane imaging velocity interferometer system for any reflector (VISAR) in hypervelocity impact study was exampled by velocity filed measurement of laser driven flyer. A streak camera and a framing camera were simultaneously used to captures the comb fringe, which allows to measure the velocity histories of different points along line segments and to measure velocity field across a plane at several times. A spatial resolution better than 10 m and a velocity resolution of 15 m/s were realized. The technique was employed to measure a temporal-spatial velocity field of Al foils flyer driven by a pulse laser, and to reveal the continuous evolution of flyers. These results demonstrate that the line and plane imaging VISAR can yield reliable experimental data for theoretical study and mathematical simulation of laser driven flyer or hypervelocity impact.