用于冲击波速度测量的自检式光纤传感系统

Self-check fiber-optic sensor system in shock-wave velocity detection

针对爆轰物理与冲击波物理实验中冲击波速度的测量,设计了一种带自检功能的光纤冲击波速度传感系统。系统采用直接测量冲击波到达固定测点时间的方式间接测量冲击波速度。传感头采用自发光式镀膜光纤探针,通过高速光电转换模块与示波器实现对冲击波到达时间的获取,由脉冲激光模块向传感通道耦合入脉冲激光,通过对光纤探针端面反射光脉冲信号的检测实现全系统功能自检以及各通道信号传输时间的测量。对泰安(PETN)样品冲击波速度进行了测量,实验结果表明:系统的冲击响应信号前沿小于5 ns,系统测量不确定度优于3 ns,计算结果与PETN标准爆速对比的误差为0.6%。系统具有可靠性高、响应速度快和时间分辨率高等特点,为爆轰物理和冲击波物理实验中冲击波速度测量提供了一种有效的测试手段。

A self-check fiber-optic sensor system was designed to measure shock wave velocity in detonation physics and shock wave physics experiment.In the system,the shock wave arrival time was measured indirectly to get the shock wave velocity.Sensing head was self-illumination type coating optical fiber probe,signal passing the high-speed photoelectric conversion module and oscilloscope,after which the shock wave arrival time was obtained.The light pulse from the pulse laser module was coupled into the sensing channel.By detecting the reflected light pulse from the end of the optical fiber probe,self-check capability of the whole system was realized and the channel signal transmission time was measured.The shock wave velocity in PETN was measured and the experiment results show that the frontier of shock response signal is less than 5 ns and the uncertainty of measurement is less than 3 ns.Compared with calculation result with the standard detonation velocity in PETN,the measurement error is 0.6%.The system has the characteristics of high reliability,fast response,and high time resolution which provides an effective test instrument for shock wave velocity measurement in detonation physics and shock wave physics.