Laser-induced fluorescence of formaldehyde in combustion using third harmonic Nd:YAG laser excitation.
Formaldehyde (CH2O) is an important intermediate species in combustion processes and it can through laser-induced fluorescence measurements be used for instantaneous flame front detection. The present study has focussed on the use of the third harmonic of a Nd:YAG laser at 355 nm as excitation wavelength for formaldehyde, and different dimethyl ether (C2H6O) flames were used as sources of formaldehyde in the experiments. The investigations included studies of the overlap between the laser profile and the absorption lines of formaldehyde, saturation effects and the potential occurrence of laser-induced photochemistry. The technique was applied for detection of formaldehyde in an internal combustion engine operated both as a spark ignition engine and as a homogenous charge compression ignition engine.
Brackmann
Christian
C
Division of Combustion Physics, Lund Institute of Technology, P.O. Box 118, SE-221 00 Lund, Sweden. christian.brackmann@forbrf.lth.se
Nygren
Jenny
J
Bai
Xiao
X
Li
Zhongshan
Z
Bladh
Henrik
H
Axelsson
Boman
B
Denbratt
Ingemar
I
Koopmans
Lucien
L
Bengtsson
Per-Erik
PE
Aldén
Marcus
M
D005453:Fluorescence; D005557:Formaldehyde / Q000737:chemistry*; D007834:Lasers; D008738:Methyl Ethers / Q000737:chemistry; D013053:Spectrophotometry
D008738:Methyl Ethers; D005557:Formaldehyde; C033413:dimethyl ether