Abstract
The mid-infrared wavelength region near 8 mu m contains absorption bands of several molecules such as water vapor, hydrogen peroxide, nitrous oxide, methane and acetylene. A new laser absorption sensor based on the v(4) band of methane and the v(4)+v(5) band of acetylene is reported for interference-free, time-resolved measurements under combustion-relevant conditions. A detailed line-selection procedure was used to identify optimum transitions. Methane and acetylene were measured at the line centers of Q12 (1303.5 cm(-1)) and P23 (1275.5 cm(-1)) transitions, respectively. High-temperature absorption cross sections of methane and acetylene were measured at peaks (on-line) and valleys (off-line) of the selected absorption transitions. The differential absorption strategy was employed to eliminate interference absorption from large hydrocarbons. Experiments were performed behind reflected shock waves over a temperature range of 1200-2200 K, between pressures of 1-4 atm. The diagnostics were then applied to measure the respective species time-history profiles during the shock-heated pyrolysis of n-pentane. (C) 2015 Elsevier Ltd. All rights reserved.
Original language | English (US) |
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Pages (from-to) | 66-74 |
Number of pages | 9 |
Journal | Journal of Quantitative Spectroscopy and Radiative Transfer |
Volume | 155 |
DOIs | |
State | Published - Apr 2015 |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledgements: Research reported in this publication was supported by the King Abdullah University of Science and Technology (KAUST) and by Saudi Aramco under the FUELCOM Program.