Measurement of soot spectral emission and error analysis based on counterflow flame
1. School of Automotive Engineering, Wuhan University of Technology, Wuhan, Hubei 430070, China; 2. Hubei Key Laboratory of Advanced Technology for Automotive Components, Wuhan University of Technology, Wuhan, Hubei 430070, China
Abstract：The distribution of temperature and soot volume fraction in the ethylene counterflow diffusion flame was measured accurately based on soot spectral emission (SSE) method. To effectively reduce the measurement error of SSE method and improve the accuracy of experiment, the numerical simulation was used to quantitatively investigate the influence of multiple factors on the measurement of temperature and soot volume fraction in the counterflow flame. The research results show that the readout noise of the spectrometer causes serious distortion in the measurement of temperature and soot volume fraction in the low temperature zone. Ignoring the self-absorption effect, the soot volume fraction is overestimated, and the temperature is underestimated, while the use of longer wavelength radiation data can reduce the influence of ignoring the self-absorption to a certain extent. The radiant intensity calibration error caused by the calibration source temperature error only affects the temperature measurement accuracy, and the diaphragm aperture error only affects the measurement accuracy of the soot volume fraction. The uncertainty of soot absorption function is the main source of error in the measurement of temperature and soot volume fraction.
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