Diagnostics of hot zones by absorption spectroscopy with diode lasers (review)

A review of the works that we have been carried in the last 5 years on the use of the method of absorption spectroscopy with diode lasers for the diagnosis of hot zone parameters is given. A spectrometer with two lasers operating in different spectral ranges with sufficiently strong absorption lines has been developed for the case of high pressures and gas temperature. The results of the search for optimal lines in different spectral ranges have been presented. The results of laboratory measurements and tests at the experimental power stand at TSAGI Named after Prof. N.E. Zhukovsky have been presented. Approaches to determining the maximum temperature for spatially inhomogeneous hot zones have been discussed. The method of difference spectra and method of fitting the experimental spectrum with the sum of one-temperature spectra have been proposed. The efficiency of the proposed processing algorithms for specific types of hot zones has been shown experimentally.