Concentration measurement of NO using self-absorption spectroscopy of the γ band system in a pulsed corona discharge.
Nitric oxide (NO) concentrations were measured using the γ band system spectrum based on the strong self-absorption effect of NO in pulsed corona discharges. The radiative transitional intensities of the NO γ band were simulated based on the theory of molecular spectroscopy. The intensities of some bands, especially γ(0,0) and γ(1,0), are weakened by the self-absorption. The correlations between the spectral self-absorption intensities and NO concentration were validated using a modified Beer-Lambert law with a combined factor K relating the branching ratio and the NO concentration, and a nonlinear index α that is applicable to the broadband system. Optical emissive spectra in pulsed corona discharges in NO and N2/He mixtures were used to evaluate the two parameters for various conditions. Good agreement between the experimental and theoretical results verifies the self-absorption behavior seen in the UV spectra of the NO γ bands.
Department of Thermal Engineering, State Key Laboratory of Power Systems, Tsinghua University, Beijing, China.
Xiaodong
X
Zhai
Yanjun
Y
Ding
Zhimin
Z
Peng
Rui
R
Luo