Research on Furnace Flame Emissivity Distribution of a Utility Boiler based on Spectral Analysis
The difference between flame gray band judgment method based on two-color method and non-linear least square method in solving the temperature and emissivity of coal-flame was evaluated.A spectrometer system was used to collect flame spectrum of a 1000 MW coal-fired boiler,and a method was used to separate the continuous baseline from the measured flame spectra.The two methods were used to solve the temperature and emissivity distribution of coal flame spectrum in the range of 650-900nm.The results show that the emissivity distribution at 35.1m and 37m calculated by flame gray band judgment method does not satisfy gray property,while the emissivity distribution calculated by non-linear least squares method satisfies gray property.This indicates that the gray band judgment method is not accurate in judging the gray band.The temperature calculated by the nonlinear least square method was combined with Planks law to find the emissivity profiles in the range of 500-900nm,indicating that the coal flame in range of 500-900nm is not completely meet the gray.The reliability of CCD imaging temperature measurement based on two-color method(R,G)was analyzed.
two-color methodspectral analysisemissivitycoal-fired flamenon-linear least squares method
万方数据
维普
