TITLE:
Research on Measurement Technology of Flue Gas Velocity Based on Optical Scintillation Induced by Fluctuation of Particulate Concentration
AUTHORS:
Zhibo Ni, Tao Pang, Yang Yang, Fengzhong Dong
KEYWORDS:
Optical Scintillation, Flue Gas Velocity, Particulate Concentration, Cross Correlation
JOURNAL NAME:
Journal of Environmental Protection,
Vol.5 No.10,
July
30,
2014
ABSTRACT:
Based on the theory of optical scintillation induced by fluctuation of
particulate concentration, a Gas Flow Velocity Measurement System (GFVMS) is
proposed to measure the gas flow velocity in stack. Verification experiments on
simulation flue indicate that, for the smoothing effect of transmitting and
receiving apertures, optical scintillation induced by refractive index fluctuation
is very weak. When particles are added into gas flow, the standard deviation of
optical scintillation increased obviously. And when the particulate number
concentration exceeds 4000/m3, the GFVMS can work normally, and the
variation range of measured velocities is almost the same with that of Pitot tube.
Sensitivity testing results show that, GFVMS is very sensitive to velocity
change. Results of outfield experiment prove that, velocities measured by GFVMS
are more stable and the average velocity (7.62/s) is very close to the
statistical average (7.61 m/s) of velocities measured by Pitot tube at
different points along optical path.