Determination of soot temperature, volume fraction and refractive index from flame emission spectrometry

An inversion scheme based on tomographic reconstruction of flame emission spectra has been developed for nonintrusive characterization of soot temperature and volume fraction fields within an optically thin axisymmetric flame by extracting characteristic information on soot refractive index from spectral gradients of emission spectra. Its performance is assessed by providing input data obtained from intensities simulated by a direct code based on experimental data for a flame available in the literature. Proposed method was found to be especially powerful in the near-infrared range for accurate prediction of flame properties where spectral variation of optical constants is significant.