|Effect of surface reflectivity on photonic Doppler velocimetry measurement|
|Wu XQ(吴先前); Xia WG(夏伟光); Wang X(王曦); Song HW(宋宏伟); Huang CG(黄晨光); Huang CG(黄晨光)
|Source Publication||Measurement Science and Technology
|Abstract||While photonic Doppler velocimetry (PDV) is becoming a common diagnostic for tracking
velocity in shock physical experiments, its validity on measuring surfaces with different
reflectivity is not studied. This paper investigates the effects of surface reflectivity on PDV
measurement for tracking back free surface velocity in laser shock processing. Credible
measurement results for coarse polished surfaces with low reflectivity are obtained, whereas
fine polished surfaces with relatively high reflectivity lead to heterodyne fringes with high
frequency and corresponding unreasonably fast velocities. This phenomenon reported in the
paper is somewhat inconsistent with the general view that PDV has remarkable robustness to
large changes in surface reflectivity. The reason might be ascribed to multiple reflections of
light, which cause the generation of multiple Doppler shifts. The mixing of the reference light
and those Doppler-shifted lights brings out high frequency heterodyne fringes resulting in high
velocity. Low surface reflectivity is better suited for PDV measurements.|
|Keyword||Onic Doppler Velocimetry
Back Free Surface Velocity
Multiple Doppler Shifts
|Funding Organization||This work is funded by the Instrument Project of Chinese Academy of Sciences (CAS) (grant no. YZ200930); additional funding is also provided by the National Natural Science Foundation of China (NNSFC) (grant no 11332011).
|Corresponding Author||Huang CG(黄晨光)|
Wu XQ,Xia WG,Wang X,et al. Effect of surface reflectivity on photonic Doppler velocimetry measurement[J]. Measurement Science and Technology,2014,25:055207.
Wu XQ,Xia WG,Wang X,Song HW,Huang CG,&黄晨光.(2014).Effect of surface reflectivity on photonic Doppler velocimetry measurement.Measurement Science and Technology,25,055207.
Wu XQ,et al."Effect of surface reflectivity on photonic Doppler velocimetry measurement".Measurement Science and Technology 25(2014):055207.