Measurement of the mid-infrared absorption spectra of ethylene (C2H4) and other molecules at high temperatures and pressures. (January 2019)

• Record Type: Journal Article
• Authors: Strand, C.L.; Ding, Y.; Johnson, S.E.; Hanson, R.K.
• Is Part Of: Journal of quantitative spectroscopy & radiative transfer. Volume 222/223(2019)
• Page Start: 122
• Page End: 129
• Publication Date: 2019-01
• Subjects: Spectrum analysis -- Periodicals; Radiation -- Periodicals; Analyse spectrale -- Périodiques; Rayonnement -- Périodiques; Radiation; Spectrum analysis; Periodicals; 543.0858
• DOI: 10.1016/j.jqsrt.2018.10.030
• Languages: English
• ISSNs: 0022-4073

Abstract

Abstract: A methodology for the measurement of mid-infrared absorption cross sections of gaseous molecules at high temperatures and pressures is presented. A rapid-tuning, broad-scan external cavity quantum cascade laser with a tuning rate in excess of 30000 cm − 1 s − 1 has been employed in the measurement of full vibrational bands ( > 100 cm − 1 ) in shock-heated test gases. The approach is demonstrated with measurements of the absorption cross section of ethylene (C2 H4 ) in the 8.5 µm to 11.7 µm region for temperatures from 800 K to 1600 K and pressures from 1 to 5 atm. Decreasing peak strength with temperature is observed as well as pressure-insensitivity. The measurements are compared with existing experimental, empirical, and ab initio databases. Additionally, illustrative absorption cross section measurements of propene (C3 H6 ), 1-butene (1-C4 H8 ), 2-butene (2-C4 H8 ), 1, 3-butadiene (1, 3-C4 H6 ), and methanol (CH3 OH) are presented near 1000 K and 2.3 atm.