Strategy for instantaneous formaldehyde (CH2O) imaging by planar laser-induced fluorescence (PLIF) in a scramjet with intense flame emissions

Wan，Minggang1; Zhu，Jiajian1; Sun，Mingbo1; Zheng，Shu2; Zhou，Bo3; Huang，Yuhui4; Wang，Hongbo1; Liu，Yao1; Wu，Ge1; Wang，Zhenguo1

2023-08-01

10.1016/j.combustflame.2023.112856

Combustion and Flame   Impact Factor & Quartile

0010-2180

1556-2921

Conducting CHO PLIF imaging in scramjets is challenging due to strong flame emissions (FEs). The FE interference is comparable to the CHO fluorescence in the wavelength range of the fluorescence. To deal with this challenge, we proposed a CHO PLIF imaging strategy considering CHO excitation at 353.06 nm and FE reduction based on capturing two frames with a reasonable time delay. The fluorescence efficiency with the 353.06 nm excitation was shown to be approximately four times that with the excitation of ∼355 nm in the linear regime, where the two wavelengths corresponded to full-width-at-half-maximum line widths of ∼0.16 and ∼1 cm, respectively. During the two frames being captured, the FE background remained nearly constant. Then collecting the CHO fluorescence in the first frame and subtracting the second frame from the first substantially reduced FE interference. The signal-to-background ratio in the raw image was approximately 1–2, but it could be increased to 10 using the proposed strategy. This strategy enables CHO PLIF imaging to be conducted in scramjets and scramjet-like combustion facilities with intense FE interference.

Formaldehyde PLIF Scramjet Supersonic combustion

SCI

English

Others

National Natural Science Foundation of China[11925207];National Natural Science Foundation of China[12172379];

Thermodynamics ; Energy & Fuels ; Engineering

Thermodynamics ; Energy & Fuels ; Engineering, Multidisciplinary ; Engineering, Chemical ; Engineering, Mechanical

WOS:001012686400001

ELSEVIER SCIENCE INC

ENGINEERING

2-s2.0-85163376918

Scopus

1.Science and Technology on Scramjet Laboratory,College of Aerospace Science and Engineering,National University of Defense Technology,Changsha,410073,China
2.National Engineering Research Center of New Energy Power Generation,North China Electric Power University,Beijing,102206,China
3.Department of Mechanics and Aerospace Engineering,Southern University of Science and Technology,Shenzhen,518055,China
4.Equipment Project Management Center,Equipment Development Department,Beijing,100089,China

Wan，Minggang,Zhu，Jiajian,Sun，Mingbo,et al. Strategy for instantaneous formaldehyde (CH2O) imaging by planar laser-induced fluorescence (PLIF) in a scramjet with intense flame emissions[J]. Combustion and Flame,2023,254.

Wan，Minggang.,Zhu，Jiajian.,Sun，Mingbo.,Zheng，Shu.,Zhou，Bo.,...&Wang，Zhenguo.(2023).Strategy for instantaneous formaldehyde (CH2O) imaging by planar laser-induced fluorescence (PLIF) in a scramjet with intense flame emissions.Combustion and Flame,254.

Wan，Minggang,et al."Strategy for instantaneous formaldehyde (CH2O) imaging by planar laser-induced fluorescence (PLIF) in a scramjet with intense flame emissions".Combustion and Flame 254(2023).