TY - JOUR
T1 - A mid-infrared diagnostic for benzene using a tunable difference-frequency-generation laser
AU - Shakfa, Mohammad Khaled
AU - Mhanna, Mhanna
AU - Jin, Hanfeng
AU - Liu, Dapeng
AU - Djebbi, Khalil
AU - Marangoni, Marco
AU - Farooq, Aamir
N1 - Funding Information:
Research reported in this publication was funded by the Office of Sponsored Research and King Abdullah University of Science and Technology (KAUST).
PY - 2021
Y1 - 2021
N2 - In combustion, benzene plays an essential role in the formation and growth of polycyclic aromatic hydrocarbons and soot. A new laser-based diagnostic is presented to make quantitative, interference-free, and sensitive measurements of benzene in the mid-infrared (MIR) region. The diagnostic is based on a widely tunable difference-frequency-generation (DFG) laser system. This laser source was developed to emit in the MIR between 666.54/cm and 790.76/cm as a result of the DFG process between an external-cavity quantumcascade-laser and a CO2 gas laser in a nonlinear, orientation-patterned GaAs crystal. Benzene measurements were carried out at the peak (673.94/cm ) of the Q-branch of the ν11 vibrational band of benzene. The absorption cross-section of benzene was measured over a range of pressures (4.44 mbar to 1.158 bar) at room temperature. The temperature dependence of the absorption cross-section was studied behind reflected shock waves over 553–1473 K. The diagnostic was demonstrated in a high-temperature reactive experiment of benzene formation from propargyl radicals. The new diagnostic will prove highly beneficial for high-temperature studies of benzene formation and consumption kinetics.
AB - In combustion, benzene plays an essential role in the formation and growth of polycyclic aromatic hydrocarbons and soot. A new laser-based diagnostic is presented to make quantitative, interference-free, and sensitive measurements of benzene in the mid-infrared (MIR) region. The diagnostic is based on a widely tunable difference-frequency-generation (DFG) laser system. This laser source was developed to emit in the MIR between 666.54/cm and 790.76/cm as a result of the DFG process between an external-cavity quantumcascade-laser and a CO2 gas laser in a nonlinear, orientation-patterned GaAs crystal. Benzene measurements were carried out at the peak (673.94/cm ) of the Q-branch of the ν11 vibrational band of benzene. The absorption cross-section of benzene was measured over a range of pressures (4.44 mbar to 1.158 bar) at room temperature. The temperature dependence of the absorption cross-section was studied behind reflected shock waves over 553–1473 K. The diagnostic was demonstrated in a high-temperature reactive experiment of benzene formation from propargyl radicals. The new diagnostic will prove highly beneficial for high-temperature studies of benzene formation and consumption kinetics.
KW - Absorption cross-section
KW - Benzene
KW - Difference frequency generation
KW - PAH formation
KW - Shock tube
UR - http://www.scopus.com/inward/record.url?scp=85091444563&partnerID=8YFLogxK
U2 - 10.1016/j.proci.2020.06.382
DO - 10.1016/j.proci.2020.06.382
M3 - Conference article
AN - SCOPUS:85091444563
SN - 1540-7489
VL - 38
SP - 1787
EP - 1796
JO - Proceedings of the Combustion Institute
JF - Proceedings of the Combustion Institute
IS - 1
T2 - 38th International Symposium on Combustion, 2021
Y2 - 24 January 2021 through 29 January 2021
ER -