A Research Of Optical Fiber Taper Machine Flame Temperature Measurement Technology Based On Multispectral Radiation

True temperature and spectral emissivity is calculated by multi-wavelength thermometry through getting spectral information at multi-wavelength.This algorithm of temperature measurement based on Planck's law.The main obstacle of this algorithm is unknown emissivity,so the true temperature can't be accurately got.The true temperature only can be calculated though inversion algorithm.Now all of the inversion algorithm needs to assume a model between emissivity and wavelength or temperature,but a model only used to a kind of target.Whether a data processing algorithm without assuming emissivity is proposed is the key of multi-wavelength thermometry.This paper studies multi-wavelength thermometry from the experiment and the algorithm,the study of this paper will make the multi-wavelength thermometry more suitable for high temperature online measuring.Data processing algorithms of multi-wavelength thermometry are mainly studied in the paper.And then the temperature of the fiber tapering machine flame is measured.The basic theory of multi-wavelength thermometry and the basic concepts of thermal radiation,blackbody and Planck's law are introduced in this paper.The three kinds of radiation temperature measuring mathematical model are given and compared.On the basis of mathematical model based on reference temperature,equation algorithm is studied in the paper.A gradient project algorithm is proposed combined with the gradient projection method in mathematics and multi-wavelength thermometry.The secondary measurement algorithm is improved to be able to use on real-time online measurement.The matlab simulation result shows that improved quadratic measurement algorithm is more suitable for online measuring in the multi-wavelength thermometry.In order to verify the usefulness of the improved second measurement algorithm,the fiber tapering machine flame temperature measurement experiment is designed.The optical aim system is designed,the temperature measuring software is written,the experimental device was calibrated and the uncertainty is analyzed.