• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.4
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• pp.91-99
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• 1994

Tunable KrF Excimer Laser is used here for measuring OH and $O_2$ density distribustion in an open $H_2$/air premixed flame and in a combustion bomb. Laser Rayleigh Scattering(LRS) and Planar Laser Induced Predissociative Fluorescence(PLIPF) methods are used to obtain two-dimensional images of total and specific densities. Laser Excitation wavelengths are calibrated via flame images and combustion bomb images show good qualitative a greement with theoretical calculation. Furthermore images in a combustion bomb can be developed to study real Spark-Ignition engine combustions. Our experimental images show that there are no more collisional quenching problem at high pressure environment(including atmospheric pressure) using predissociative fluorescence technique. Further development to obtain two-dimensional temperature dustribution is ready to use eventhough it is not reported in this paper.

• Transactions of the Korean hydrogen and new energy society
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• v.13 no.3
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• pp.169-180
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• 2002

Rayleigh scattering and laser induced predissociative fluorescence are used to obtain two-dimensional images of temperature and species concentration in a laminar non-premixed flame of a diluted hydrogen jet. Rayleigh scattering cross-sections are experimentally obtained at 248nm. Planar images of OH and $O_2$ with tunable KrF excimer laser which has a) $0.5cm^{-1}$ linewidth, b) 0.5nm tuning range, c) 150mJ pulse energy, and d) 20ns pulse width are obtained to determine spatial distributions of OH and $O_2$. The technique is based on planar laser induced predissociative fluorescence (PLIPF) in which collisional quenching is almost avoided because of the fast predissociation. Dispersed LIPF spectra of OH and $O_2$ are also measured in a flame in order to confirm the excitation of single vibronic state of OH and $O_2$. OH and $O_2$ are excited on the $P_2$(8) and $Q_1$(11) line of the $A^2{\Sigma}^{+}({\nu}^{'}=3)-X^{2}{\Pi}({\nu}^{''}=o)$ band and R(17) line of the Schumann-Runge band $B^{3}{\Sigma}_{u}{^-}(\nu^{'}=0)-X^{3}{\Sigma}_{g}{^-}({\nu}^{''}=6)$, respectively. Fluorescence spectra of OH and Hot $O_2$ are captured and two-dimensional images of the hydrogen flame field are successfully visualized.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.12
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• pp.1582-1582
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• 2000

Rayleigh scattering and laser induced predissociative fluorescence are employed for capturing two-dimensional images of temperature and species concentration in a laminar nonpremixed flame of a diluted hydrogen jet. Rayleigh scattering cross-sections are experimentally obtained at 248nm. Dispersed LIPF spectra of OH and O₂ are also measured in a flame in order to confirm the excitation of single vibronic state of OH and O₂are excited on the P₁(8) line of the A ²∑+ (v＇=3) - X ²∏(v˝=0) band and R(17) line of the Schumann-Runge band B ³∑u- (v＇=0) - X ³∑g-∏(v˝=6), respectively. Fluorescence spectra of OH and Hot O₂ are captured and two-dimensional images of the hydrogen flame field are successfully visualized.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.12
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• pp.1580-1587
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• 2000

Rayleigh scattering and laser induced predissociative fluorescence are employed for capturing two-dimensional images of temperature and species concentration in a laminar nonpremixed flame of a diluted hydrogen jet. Rayleigh scattering cross-sections are experimentally obtained ar 248nm. Dispersed LIPF spectra of OH and O$_2$ are also measured in a flame in order to confirm the excitation of single vibronic state of OH and O$_2$ .OH and O$_2$ are excited on the P$_1$(8) line of the A $^2\Sigma ^+(v^`=3) - X^2\pi (V^"=0)$ band and R(17) line of the Schumann-Runge band B $^3\Sigma _u^-(v^`=0) - X ^3\Sigma _g^-(v^"=6)$, respectively. Fluorescence spectra of OH and Hot O$_2$ are captured and two-dimensional images of the hydrogen flame field are successfully visualized.