Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9599070 | Journal of Quantitative Spectroscopy and Radiative Transfer | 2005 | 28 Pages |
Abstract
We present a theoretical study of the spectral interferences in the spontaneous Raman scattering spectra of major combustion products in 30-atm fuel-rich H2-air flames. An effective methodology is introduced to choose an appropriate line-shape model for simulating Raman spectra in high-pressure combustion environments. The Voigt profile with the additive approximation assumption was found to provide a reasonable model of the spectral line shape for the present analysis. The rotational/vibrational Raman spectra of H2, N2, and H2O were calculated using an anharmonic-oscillator model using the latest collisional broadening coefficients. The calculated spectra were validated with data obtained in a 10-atm fuel-rich H2-air flame and showed excellent agreement. Our quantitative spectral analysis for equivalence ratios ranging from 1.5 to 5.0 revealed substantial amounts of spectral cross-talk between the rotational H2 lines and the N2O-/Q-branch; and between the vibrational H2O(0,3) line and the vibrational H2O spectrum. We also address the temperature dependence of the spectral cross-talk and extend our analysis to include a cross-talk compensation technique that removes the interference arising from the H2 Raman spectra onto the N2, or H2O spectra.
Related Topics
Physical Sciences and Engineering
Chemistry
Spectroscopy
Authors
Jun Kojima, Quang-Viet Nguyen,