Research on Measurement Technology of Flue Gas Velocity Based on Optical Scintillation Induced by Fluctuation of Particulate Concentration

Zhibo Ni, Tao Pang, Yang Yang, Fengzhong Dong

Anhui Provincial Key Laboratory of Photonic Devices and Materials, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei, China.

DOI: 10.4236/jep.2014.510092                

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.

Keywords

Optical Scintillation, Flue Gas Velocity, Particulate Concentration, Cross Correlation

Conflicts of Interest

The authors declare no conflicts of interest.

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