This study conducts a comprehensive analysis of the coherent structures within a spatially developing underexpanded axisymmetric jet at a Reynolds number of 45 000, utilizing high-fidelity implicit large eddy simulations (iLES) in conjunction with spectral proper orthogonal decomposition (SPOD). In the frequency–wavenumber space, the global SPOD analysis identifies three distinct coherent structures, corresponding to three different mechanisms, namely, Kelvin–Helmholtz (KH), Orr, and lift-up. Their salient characteristics are discussed in detail. Local SPOD analysis further explores the streamwise evolution of these coherent structures, revealing that the influence of KH mechanism is confined to the near field, while the lift-up mechanism persists and dominates the energy content beyond the potential core, with the streaks of azimuthal wavenumbers one and two being the most energetic. The reconstruction of turbulent kinetic energy (TKE) and Reynolds shear stress from SPOD modes is assessed, and the first few azimuthal modes with low wavenumbers and frequencies are found crucial for capturing the dominant features of the flow. It is found that only the m = 0 and m = 1 modes contribute to the TKE at the centerline. The Reynolds shear stress reconstruction quality is comparable to TKE, but with a negligible contribution from the m = 0 mode. The azimuthal mode m = 1 captures the slope of the actual Reynolds shear stress profile in the vicinity of centerline, while m = 2 and higher modes capture the peak location of the actual profile.
Skip Nav Destination
Article navigation
October 2024
Research Article|
October 25 2024
Spectral proper orthogonal decomposition analysis of a spatially developing underexpanded round jet at Re = 45 000
Rui Wang (王锐);
Rui Wang (王锐)
(Data curation, Formal analysis, Investigation, Methodology, Validation, Visualization, Writing – original draft)
1
School of Aeronautics and Astronautics, Shanghai Jiao Tong University
, Shanghai 200240, China
Search for other works by this author on:
Feng Wu (吴锋)
;
Feng Wu (吴锋)
(Methodology, Software, Writing – review & editing)
2
AECC Sichuan Gas Turbine Establishment
, Mianyang 621000, China
Search for other works by this author on:
Haoqi Fei (费浩锜)
;
Haoqi Fei (费浩锜)
(Data curation, Methodology, Validation)
1
School of Aeronautics and Astronautics, Shanghai Jiao Tong University
, Shanghai 200240, China
Search for other works by this author on:
Xiaojing Wang (王晓晶);
Xiaojing Wang (王晓晶)
a)
(Methodology, Supervision)
3
Advanced Interdisciplinary Technology Research Center, National Innovation Institute of Defense Technology
, 100071 Beijing, China
a)Authors to whom correspondence should be addressed: wang_xiaojing90@163.com and dr.hxu@sjtu.edu.cn
Search for other works by this author on:
Hui Xu (徐辉)
Hui Xu (徐辉)
a)
(Conceptualization, Funding acquisition, Project administration, Resources, Supervision)
1
School of Aeronautics and Astronautics, Shanghai Jiao Tong University
, Shanghai 200240, China
a)Authors to whom correspondence should be addressed: wang_xiaojing90@163.com and dr.hxu@sjtu.edu.cn
Search for other works by this author on:
a)Authors to whom correspondence should be addressed: wang_xiaojing90@163.com and dr.hxu@sjtu.edu.cn
Physics of Fluids 36, 105195 (2024)
Article history
Received:
August 07 2024
Accepted:
October 07 2024
Citation
Rui Wang, Feng Wu, Haoqi Fei, Xiaojing Wang, Hui Xu; Spectral proper orthogonal decomposition analysis of a spatially developing underexpanded round jet at Re = 45 000. Physics of Fluids 1 October 2024; 36 (10): 105195. https://doi.org/10.1063/5.0232434
Download citation file:
Sign in
Don't already have an account? Register
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Pay-Per-View Access
$40.00
155
Views
Citing articles via
On Oreology, the fracture and flow of “milk's favorite cookie®”
Crystal E. Owens, Max R. Fan (范瑞), et al.
A unified theory for bubble dynamics
A-Man Zhang (张阿漫), 张阿漫, et al.
Computational fluid–structure interaction in biology and soft robots: A review
R. Pramanik, R. W. C. P. Verstappen, et al.
Related Content
Research on spectral estimation parameters for application of spectral proper orthogonal decomposition in train wake flows
Physics of Fluids (December 2021)
Spectral feature extraction of rocket exhaust plume using spectral proper orthogonal decomposition
Physics of Fluids (March 2024)
Flow field characteristics of a confined, underexpanded transient round jet
Physics of Fluids (August 2021)
Large-eddy simulation of highly underexpanded transient gas jets
Physics of Fluids (January 2013)
Vortex breakdown of the swirling flow in a Lean Direct Injection burner
Physics of Fluids (December 2020)