4 November 2016 Impacts of PM concentrations on visibility impairment
Author Affiliations +
Abstract
In the paper, an accurate and sensitive cavity attenuated phase shift spectroscopy (CAPS) sensor was used to monitor the atmospheric visibility. The CAPS system mainly includes a LED light source, a band-pass filter, an optical resonant cavity (composed of two high mirror, reflectivity is greater than 99.99%), a photoelectric detector and a lock-in amplifier. The 2L/min flow rate, the optical sensor rise and fall response time is about 15 s, so as to realize the fast measurement of visibility. An Allan variance analysis was carried out evaluating the optical system stability (and hence the maximum averaging time for the minimum detection limit) of the CAPS system. The minima (~0.1 Mm-1) in the Allan plots show the optimum average time (~100s) for optimum detection performance of the CAPS system. During this period, the extinction coefficient was correlated with PM2.5 mass (0.88), the extinction coefficient was correlated with PM10 mass (0.85). The atmospheric visibility was correlated with PM2.5 mass (0.74). The atmospheric visibility was correlated with PM10 mass (0.66).
© (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Guo Jie, Mei-mei Wang, Ye-Xing Han, Zhi-Wei Yu, Huai-Wu Tang, "Impacts of PM concentrations on visibility impairment", Proc. SPIE 10026, Real-time Photonic Measurements, Data Management, and Processing II, 100261C (4 November 2016); doi: 10.1117/12.2247767; https://doi.org/10.1117/12.2247767
PROCEEDINGS
7 PAGES


SHARE
Back to Top