TY - JOUR
T1 - Blowout limits of inclined nonpremixed turbulent jet flames
AU - Wang, Qiang
AU - Liang, Xuan
AU - Lu, Aquan
AU - Wang, Ben
AU - Fujita, Osamu
AU - Chung, Suk Ho
AU - Hu, Longhua
N1 - KAUST Repository Item: Exported on 2023-07-17
Acknowledgements: This work was supported by National Key R&D Program of China (No. 2021YFA0716203), National Natural Science Foundation of China (NSFC) (51976051, 52225605), International Partnership Program of Chinese Academy of Sciences (No. 211134KYSB20200010), Chinese Space Station Science Experiment Project (No. ZDBS-ZRKJZ-TLC012), Opening Fund of State Key Laboratory of Fire Science (SKLFS) (No. HZ2022-KF06) and Fundamental Research Funds for the Central Universities of China (No. JZ2022HGPA0310). This work was also supported by JSPS Fellowship (ID: P21343). SHC was supported by KAUST.
PY - 2023/6/7
Y1 - 2023/6/7
N2 - The blowout behavior of inclined nonpremixed turbulent jet flames is investigated by varying the jet inclined angle in the range of -90° to 90° The critical jet velocity at blow-out limit is quantified experimentally for various nozzle diameters, different fuels and inclined angles. Numerical simulations are performed to emphasize the flow field difference for the positive and negative inclined angles. Physical modeling is conducted to incorporate the effect of the inclined angle on blow-out behavior. Major findings include: (1) The negatively inclined jet flames show more intense yellow luminosity with larger sooting zones than the positively inclined jet flames; (2) The blowout limit decreases appreciably with the jet inclined angle for the negatively inclined flames, while for the positively inclined jet flames, this decrease is relatively small; (3) Physical analysis of the flow development of inclined jets is conducted, indicating the centerline velocity along the jet trajectory decreases faster for the flame with smaller inclined angle. And the decrease rate is relatively larger for the negatively inclined jet flames; (4) Based on the analysis of the flow development as well as the characteristic velocity with the inclined angle variation, a model based on the Damköhler number (Da) accounting for the effect of jet inclined angle is developed to characterize the blowout limits of inclined jet flames. The proposed model successfully correlates the experimental data. The present findings provide new data and a basic scaling law for the blowout limit of nonpremixed inclined turbulent jet flames, revealing the effect of the relative angle between the jet momentum and buoyancy.
AB - The blowout behavior of inclined nonpremixed turbulent jet flames is investigated by varying the jet inclined angle in the range of -90° to 90° The critical jet velocity at blow-out limit is quantified experimentally for various nozzle diameters, different fuels and inclined angles. Numerical simulations are performed to emphasize the flow field difference for the positive and negative inclined angles. Physical modeling is conducted to incorporate the effect of the inclined angle on blow-out behavior. Major findings include: (1) The negatively inclined jet flames show more intense yellow luminosity with larger sooting zones than the positively inclined jet flames; (2) The blowout limit decreases appreciably with the jet inclined angle for the negatively inclined flames, while for the positively inclined jet flames, this decrease is relatively small; (3) Physical analysis of the flow development of inclined jets is conducted, indicating the centerline velocity along the jet trajectory decreases faster for the flame with smaller inclined angle. And the decrease rate is relatively larger for the negatively inclined jet flames; (4) Based on the analysis of the flow development as well as the characteristic velocity with the inclined angle variation, a model based on the Damköhler number (Da) accounting for the effect of jet inclined angle is developed to characterize the blowout limits of inclined jet flames. The proposed model successfully correlates the experimental data. The present findings provide new data and a basic scaling law for the blowout limit of nonpremixed inclined turbulent jet flames, revealing the effect of the relative angle between the jet momentum and buoyancy.
UR - http://hdl.handle.net/10754/692991
UR - https://linkinghub.elsevier.com/retrieve/pii/S1540748922005272
UR - http://www.scopus.com/inward/record.url?scp=85144200723&partnerID=8YFLogxK
U2 - 10.1016/j.proci.2022.11.009
DO - 10.1016/j.proci.2022.11.009
M3 - Article
SN - 1873-2704
VL - 39
SP - 2389
EP - 2398
JO - PROCEEDINGS OF THE COMBUSTION INSTITUTE
JF - PROCEEDINGS OF THE COMBUSTION INSTITUTE
IS - 2
ER -