LIF Spectroscopy of NO and O₂ in High-Pressure Flames

Abstract

We report new models of absorption, excitation, and fluorescence spectra for joint excitations of the A ← X(0,0) band of NO and the B← X bands of 0₂. Supporting measurements obtained from the burned regions of flames operated at pressures from 1 to 10 atm are also presented. As developed through these models, a strategy appropriate for imaging planar laser-induced flourescence is proposed that, for lean combustion environments, should afford sensitive measurements of NO concentration through the use of a single excitation wavelength despite the photolytic interference from 0₂ that intensifies with increasing pressure and temperature.

Keywords:

• NO
• O₂
• gamma bands
• Schumann-Runge bands
• laser-induced fluorescence
• combustion