IDENTIFICATION OF MOLECULAR BANDS IN THE PLASMA EMISSION SPECTRA INSIDE THE LOW-EMISSION COMBUSTION CHAMBER
In the plasma emission spectra inside the low-emission combustion chamber of a gas turbine engine, the following molecular bands were identified (the most intense edges are given in parentheses): OH (306.1 nm), CH (430.18 nm), H2O (714-980 nm), C2 (515.55 nm), NH (336 nm), and NO (358.26 nm). This offers a possibility of using the ratio of their intensities to control the operating parameters of the combustion chamber to reduce harmful emissions regulated by ICAO standards. The spectra are recorded by Kolibri-2 spectrometers in two versions: 1) operating spectral range of 190-1100 nm with a resolution of 1 nm and 2) operating spectral range of 190-360 nm with a resolution of 0.2 nm. The plasma emission is coupled to the spectrometer using an optical fiber and a collimator.