Trajectory and velocity measurement of a particle in spray by digital holography.
We present a method for the trajectory and the velocity measurement of a particle in spray by digital holography. Based on multiple exposure digital in-line holography, a sequence of digital holograms of a dynamic spray particle field at different times are recorded with a CW laser and a high-speed CCD. The time evolution of the serial positions of particles, i.e., the motion trajectories of the particles, is obtained by numerically reconstructing the synthetic hologram of a sequence of digital holograms. The center coordinate (x,y) of each particle image can be extracted using a Hough transform and subpixel precision computing, and the velocity of an individual particle can also be obtained, which is then applied to measuring the velocity of diesel spray and alcohol spray. The research shows that the method presented in this paper for measuring spray field is feasible.
Lü
Qieni
Q
College of Precision Instruments & Optoelectronics Engineering, Tianjin University, Key Laboratory of Opto-electronics Information and Technical Science, Ministry of Education, Tianjin 300072, China. qienil@tju.edu.cn
Chen
Yiliang
Y
Yuan
Rui
R
Ge
Baozhen
B
Gao
Yan
Y
Zhang
Yimo
Y