Abstract
This work describes the development of a dual-pump coherent anti-Stokes Raman spectroscopy system for simultaneous measurements of the temperature and the absolute mole fraction of N-2, O-2, and H-2 in supersonic combusting flows. Changes to the experimental setup and the data analysis to improve the quality of the measurements in this turbulent, high-temperature reacting flow are described. The accuracy and precision of the instrument have been determined using data collected in a Hencken burner flame. For temperatures above 800 K, errors in the absolute mole fraction are within 1.5%, 0.5%, and 1% of the total composition for N-2, O-2, and H-2, respectively. Standard deviations based on 500 single shots are between 10 and 65 K for the temperature, between 0.5% and 1.7% of the total composition for O-2, and between 1.5% and 3.4% for N-2. The standard deviation of H-2 is similar to 10% of the average measured mole fraction. (C) 2013 Optical Society of America