Simultaneous and time-resolved temperature and relative CO2-N2 and O2-CO2-N2 concentration measurements with pure rotational coherent anti-Stokes Raman scattering for pressures as great as 5 MPa

Journal Article · Sat Sep 10 00:00:00 EDT 2005 · Applied Optics

DOI:https://doi.org/10.1364/AO.44.005582· OSTI ID:20702631

Schenk, Martin; Seeger, Thomas; Leipertz, Alfred

Pure rotational coherent anti-Stokes Raman-scattering (CARS) measurements have been performed in binary CO2-N2 and ternary CO2-O2-N2 mixtures in a temperature range between 300 and 773 K and pressures from 0.1 to 5 MPa to prove its potential for simultaneous single-shot thermometry and multispecies concentration measurements. In pressurized systems the CO2 component has a strong spectral influence on the pure rotational CARS spectra. Because of this dominance, pure rotational CARS proves to be a sensitive tool to measure in high-pressure combustion systems and the relative CO2-N2 concentration in the lower temperature range simultaneously with the temperature and the relative O2-N2 concentration. The evaluation of the spectra utilized a least-sum-squared differences fit of the spectral shape, weighted either constantly or inversely with respect to the normalized signal intensity. The results of the simultaneous temperature and relative CO2-N2 and O2-CO2-N2 concentration measurements provided a good accuracy and precision both in temperature and in concentrations. Because of the strong increase in the relative spectral contribution of CO2 with rising pressure, the precision of the CO2 concentration determination is in general significantly improved toward higher pressures, thus also clearly enhancing the CO2 detectability. The influence of temperature, O2 and CO2 concentration, pressure, and the evaluation techniques employed on both the accuracy and the precision is explained as well as their cross dependencies. The influence and limitations of the approximations used to model the CO2 molecule are discussed.

• OSTI ID: 20702631
• Journal Information: Applied Optics, Vol. 44, Issue 26; Other Information: DOI: 10.1364/AO.44.005582; (c) 2005 Optical Society of America; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6935
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CARBON DIOXIDE
COMBUSTION
MIXTURES
NITROGEN
NONLINEAR OPTICS
OXYGEN
PRESSURE DEPENDENCE
PRESSURE RANGE KILO PA
PRESSURE RANGE MEGA PA 01-10
RAMAN EFFECT
RAMAN SPECTRA
SPECTROSCOPY
TEMPERATURE DEPENDENCE
TEMPERATURE MEASUREMENT
TEMPERATURE RANGE 0273-0400 K
TEMPERATURE RANGE 0400-1000 K
TIME RESOLUTION