LAUSR

Abstract A candle flame is experimentally studied using a hyperspectral imaging device in this paper. The distributions of temperature and wavelength-dependent emissivity are calculated using a Newton-type iterative method. The results show that the spectral radiation intensity increases from the outside to the inside in the candle flame, and at the same spatial point, the intensity increases as the wavelength increases. The highest temperature of the candle flame is about 1980 K, occurs close to the flame border, indicating the most vigorous reaction. Additionally, the radiation characteristics of the candle flame differ from a gray-body, and the emissivity of the flame decreases as the wavelength increases.