基于光纤干涉系统非接触冲击波速度测试

Non contact shock-wave velocity testing based on optical-fiber interference system

根据轻气炮冲击波速度测试实验的特点与需求,提出一种新型可适用于强冲击实验的全光纤非接触速度测量技术:设计大孔径双胶合透镜组取代传统自聚焦透镜作为光收发装置,以提高系统回光抗偏转能力;应用全反棱镜改变传统测试光路,保证光探头的重复使用,以适应弹道测试系统的需求;引入直流检测端,为干涉条纹的信号处理和系统内触发提供便利。利用该方法在轻气炮速度测速试验中测量轻气弹飞行速度,其测量结果与经验值吻合。该新型冲击波速度测量技术实现了对被测体较长时间段的速度测试,其设备结构简单、灵敏度高、适应性强,可广泛应用于各领域。

According to the characteristics and requirements of light-gas gun shock-wave velocity testing experiments, this paper proposes a new method of all optical fiber non-contact velocity measurement suitable for strong impact experiment. A large aperture doublet optical transceiver system is designed to replace the traditional self-focusing lens, which improves the return light capacity of the system. A total reflection prism is used to change traditional light-path to ensure the repeat usage of the light detector and fit the requirements of the ballistic test system. A DC probe is adopted for real-time monitoring of the light intensity to simplify signal analysis and provide trigger signal. The proposed method was used in velocity test experiment of light-gas gun, and experiment results show that the tested values are consistent with experiential values. The proposed new shock wave velocity measurement technology features simple structure, high sensitivity and adaptability, can realize long time period velocity measurement, and could be widely used in various application fields.