基于裸光纤探头的双点光子多普勒测速系统

全光纤光子多普勒速度测量(PDV)系统是一种新型的激光测速系统,可广泛用于冲击波、爆轰波以及其他短时高速运动物体的速度测量。多点测量可以获得靶面不同位置的速度,以测量靶面的形变。为提高测量的空间分辨率,提出使用裸光纤束为PDV系统的探头,并在实验上实现了空间分辨率为375μm的双点速度测量。裸光纤探头的间距较小,一个探头的测量结果可能受到另一个探头反射光的干扰。理论和实验的研究结果表明,当靶面各点速度相同时,测量结果不受干扰光的影响;当各点速度不同时,其测速误差不但与两被测点的速度差有关,还与传感光和干扰光的光强和相位有关。

Two-Point Photonic Doppler Velocimetry System Based on Bare Fiber Probe

Photonic Doppler velocimetry (PDV) is a new type of laser velocimetry system. It is widely used in the velocity measurement of the shock wave, detonation wave and other short-time high-velocity moving objects. The velocities of different points of the target can be obtained using the multi-point measurement so as to find out the deformation of the target surface. It is proposed to use bare fiber bundle as probe of PDV system to improve the spatial resolution of measurement. Two-point velocity measurement with spatial resolution of 375 μm is experimentally realized. Because of smaller probe spacing, the measuring results obtained from a probe could be influenced by the reflected light from another probe. Theoretical and experimental results show that the measuring results are not affected by the stray light when the points on the target surface have the same velocity, and the measuring errors are related not only with the velocity difference of two points but also with the intensities and phases of sensing and stray light when the points on the target surface have different velocities.