摘要A zero-crossing dynamic speckle method is proposed to determine the velocities of nanoparticles in nanofluids. A Gaussian laser beam is used to illuminate nanofluids in a pipe, and the dynamic speckles are detected by a spatially integrating detector with an aperture. The integrated speckle intensity signal is processed by a computer and the zero-crossing rate is counted. The velocity of the nanoparticles can be determined from its relationship to zero-crossing rate. The results show that the nanoparticles exhibit features of flowing nanofluids, and when the average velocity of the nanofluids is 53.4 mm/s, the average velocity of the nanoparticles is 51.8±5.1 mm/s.
Abstract：A zero-crossing dynamic speckle method is proposed to determine the velocities of nanoparticles in nanofluids. A Gaussian laser beam is used to illuminate nanofluids in a pipe, and the dynamic speckles are detected by a spatially integrating detector with an aperture. The integrated speckle intensity signal is processed by a computer and the zero-crossing rate is counted. The velocity of the nanoparticles can be determined from its relationship to zero-crossing rate. The results show that the nanoparticles exhibit features of flowing nanofluids, and when the average velocity of the nanofluids is 53.4 mm/s, the average velocity of the nanoparticles is 51.8±5.1 mm/s.
YAN Qin,LU Jian,NI Xiao-Wu**. Measurement of the Velocities of Nanoparticles in Flowing Nanofluids using the Zero-Crossing Laser Speckle Method[J]. 中国物理快报, 2012, 29(4): 44207-044207.
YAN Qin,LU Jian,NI Xiao-Wu**. Measurement of the Velocities of Nanoparticles in Flowing Nanofluids using the Zero-Crossing Laser Speckle Method. Chin. Phys. Lett., 2012, 29(4): 44207-044207.
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2012, Vol. 29 
