Abstract
Medium resolution transmissivities of CO2 were measured at temperatures between 300 and 1550 K for the 4.3, 2.7 and 2:0 m bands. Measurements were made with a new drop tube design, which guarantees a truly isothermal high-temperature gas column. Data were collected with an FTIR-spectrometer, allowing for much better spectral resolution than most previous high-temperature measurements. The measured data were compared with two line-by-line and two narrow band databases. The data show some discrepancies with high-resolution databases at higher temperatures, indicating missing and=or incorrectly extrapolated spectral lines. ? 2002 Elsevier Science Ltd. All rights reserved.
Keywords: Radiative properties; Transmissivity; Narrowband; Carbon dioxide; High temperature
1. Introduction
Knowledge of radiative properties of combustion gases is required to accurately predict radiative >uxes in a number of physical systems like @res and combustion systems. Unfortunately, absorption coeBcients of absorbing gases are not known with suBcient accuracy to make reliable heat transfer calculations, especially at high temperatures. Gas spectra broadened by N2, air and other buDer gases have been studied by a number of investigators, some in the atmosphere and others in alaboratory setting. Atmospheric measurements are done using the absorbing gas that is present in the atmosphere. For example, Rinsland et al. [1] describe atmospheric measurements of water vapor properties using an FTIR spectrometer and a telescope. Atmospheric ozone measurements have been made by Bouazza et al. [2] and Flaud et al. [3]. Both these measurements were done with FTIR spectrometers. Farrenq et al. [4] have made atmospheric measurements of solar CO lines, also with an FTIR spectrometer. Atmospheric measurements have the advantage of long optical paths. However,
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http://www.ziddu.com/download/15072424/ediumresolutiontransmissionmeasurementsofCO2athigh.pdf.html
Medium resolution transmissivities of CO2 were measured at temperatures between 300 and 1550 K for the 4.3, 2.7 and 2:0 m bands. Measurements were made with a new drop tube design, which guarantees a truly isothermal high-temperature gas column. Data were collected with an FTIR-spectrometer, allowing for much better spectral resolution than most previous high-temperature measurements. The measured data were compared with two line-by-line and two narrow band databases. The data show some discrepancies with high-resolution databases at higher temperatures, indicating missing and=or incorrectly extrapolated spectral lines. ? 2002 Elsevier Science Ltd. All rights reserved.
Keywords: Radiative properties; Transmissivity; Narrowband; Carbon dioxide; High temperature
1. Introduction
Knowledge of radiative properties of combustion gases is required to accurately predict radiative >uxes in a number of physical systems like @res and combustion systems. Unfortunately, absorption coeBcients of absorbing gases are not known with suBcient accuracy to make reliable heat transfer calculations, especially at high temperatures. Gas spectra broadened by N2, air and other buDer gases have been studied by a number of investigators, some in the atmosphere and others in alaboratory setting. Atmospheric measurements are done using the absorbing gas that is present in the atmosphere. For example, Rinsland et al. [1] describe atmospheric measurements of water vapor properties using an FTIR spectrometer and a telescope. Atmospheric ozone measurements have been made by Bouazza et al. [2] and Flaud et al. [3]. Both these measurements were done with FTIR spectrometers. Farrenq et al. [4] have made atmospheric measurements of solar CO lines, also with an FTIR spectrometer. Atmospheric measurements have the advantage of long optical paths. However,
Link Full Download
http://www.ziddu.com/download/15072424/ediumresolutiontransmissionmeasurementsofCO2athigh.pdf.html
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