TY - JOUR
T1 - Large eddy simulations of the impact of swirler installation angle on flow instability in combustion chamber
AU - Meng, Nan
AU - Kang, Huifang
AU - Zhang, Lingxiao
AU - Jiang, Yifan
AU - Liang, Xu
N1 - Publisher Copyright:
© 2025
PY - 2025/12
Y1 - 2025/12
N2 - Unsteady vortex structures and periodic fluctuations affect the stability of the flow field, reducing the reliability and lifespan of the combustion chamber. This study investigates the influence of the swirler structure on the unsteady flow characteristics of a cold flow field within a center-staged combustion chamber using large eddy simulation and the power spectral density method. The results show two prominent large-scale vortex structures: the precessing vortex core (PVC) and contraction vortex core (CVC). Moreover, changes in the swirler blade angle significantly affect the unsteady flow characteristics of the coaxial staged combustion chamber. The spatial evolution of the PVC is more sensitive to changes in the pilot stage swirler, with the maximum oscillation energy reaching 15,775, which is 65 % higher than that of the baseline case. Fast Fourier transform results reveal two dominant frequencies in the combustion chamber: high-frequency (1,629.9 Hz) and low frequency (19.9 Hz). The flow field transitions from high-frequency oscillations dominated by the PVC to low-frequency oscillations driven by Kelvin–Helmholtz instability. The dominant frequency and oscillation energy amplitude distributions in the flow field exhibit specific regional characteristics. These findings offer deeper insights into the mechanisms by which swirler structures influence the unsteady flow characteristics of the combustion chamber flow field.
AB - Unsteady vortex structures and periodic fluctuations affect the stability of the flow field, reducing the reliability and lifespan of the combustion chamber. This study investigates the influence of the swirler structure on the unsteady flow characteristics of a cold flow field within a center-staged combustion chamber using large eddy simulation and the power spectral density method. The results show two prominent large-scale vortex structures: the precessing vortex core (PVC) and contraction vortex core (CVC). Moreover, changes in the swirler blade angle significantly affect the unsteady flow characteristics of the coaxial staged combustion chamber. The spatial evolution of the PVC is more sensitive to changes in the pilot stage swirler, with the maximum oscillation energy reaching 15,775, which is 65 % higher than that of the baseline case. Fast Fourier transform results reveal two dominant frequencies in the combustion chamber: high-frequency (1,629.9 Hz) and low frequency (19.9 Hz). The flow field transitions from high-frequency oscillations dominated by the PVC to low-frequency oscillations driven by Kelvin–Helmholtz instability. The dominant frequency and oscillation energy amplitude distributions in the flow field exhibit specific regional characteristics. These findings offer deeper insights into the mechanisms by which swirler structures influence the unsteady flow characteristics of the combustion chamber flow field.
KW - Aero-engine
KW - Central graded combustion chamber
KW - Pattern factor
KW - Periodic oscillation
KW - Unsteady characteristics
UR - https://www.scopus.com/pages/publications/105022060521
U2 - 10.1016/j.tsep.2025.104344
DO - 10.1016/j.tsep.2025.104344
M3 - Article
AN - SCOPUS:105022060521
SN - 2451-9049
VL - 68
JO - Thermal Science and Engineering Progress
JF - Thermal Science and Engineering Progress
M1 - 104344
ER -