TY - JOUR
T1 - Two-dimensional visualization of induction zone in hydrogen detonations
AU - Rojas Chavez, Samir B.
AU - Chatelain, Karl P.
AU - Lacoste, Deanna
N1 - KAUST Repository Item: Exported on 2023-07-18
Acknowledged KAUST grant number(s): BAS/1/1396-01-01
Acknowledgements: This work was funded by the King Abdullah University of Science and Technology (KAUST) through the baseline funding (BAS/1/1396-01-01)
PY - 2023/6/22
Y1 - 2023/6/22
N2 - The induction zone length is an important length scale for gaseous detonations, as it is correlated with other characteristic parameters such as the cell size. A good characterization of the induction zone can then lead to a better comprehension of the detonation structure. In this context, this study investigates two-dimensional (2D) visualizations of induction zones in stoichiometric hydrogen-air and hydrogen-oxygen-nitrogen-argon mixtures. The detonation speed for both mixtures is close to the Chapman Jouguet speed, and without wall losses. Planar laser-induced fluorescence (PLIF) technique was employed, by exciting nitric oxide (NO) molecules (i.e., NO-PLIF). In both mixtures, 1900 ppm of NO was added as a tracer to ensure a good signal-to-noise ratio in the von Neumann condition. The NO-PLIF images displayed a variation of the experimental induction length along the cellular cycle. Large and short induction lengths were observed for incident shock and Mach stem, respectively. A total of 2727 experimental induction lengths were extracted from the NO-PLIF images, among 79 individual experiments. Statistical analyses of these data showed that the mixture with lower activation energy exhibited less dispersion of the data compared to the mixture with higher activation energy. Non-equilibrium effects were not observed in the fluorescence profiles and induction length measurements.
AB - The induction zone length is an important length scale for gaseous detonations, as it is correlated with other characteristic parameters such as the cell size. A good characterization of the induction zone can then lead to a better comprehension of the detonation structure. In this context, this study investigates two-dimensional (2D) visualizations of induction zones in stoichiometric hydrogen-air and hydrogen-oxygen-nitrogen-argon mixtures. The detonation speed for both mixtures is close to the Chapman Jouguet speed, and without wall losses. Planar laser-induced fluorescence (PLIF) technique was employed, by exciting nitric oxide (NO) molecules (i.e., NO-PLIF). In both mixtures, 1900 ppm of NO was added as a tracer to ensure a good signal-to-noise ratio in the von Neumann condition. The NO-PLIF images displayed a variation of the experimental induction length along the cellular cycle. Large and short induction lengths were observed for incident shock and Mach stem, respectively. A total of 2727 experimental induction lengths were extracted from the NO-PLIF images, among 79 individual experiments. Statistical analyses of these data showed that the mixture with lower activation energy exhibited less dispersion of the data compared to the mixture with higher activation energy. Non-equilibrium effects were not observed in the fluorescence profiles and induction length measurements.
UR - http://hdl.handle.net/10754/693040
UR - https://linkinghub.elsevier.com/retrieve/pii/S0010218023002869
UR - http://www.scopus.com/inward/record.url?scp=85163151587&partnerID=8YFLogxK
U2 - 10.1016/j.combustflame.2023.112905
DO - 10.1016/j.combustflame.2023.112905
M3 - Article
SN - 0010-2180
VL - 255
SP - 112905
JO - Combustion and Flame
JF - Combustion and Flame
ER -