Understanding the role of flow dynamics in thermoacoustic combustion instability

J O'Connor - Proceedings of the Combustion Institute, 2023 - Elsevier
Thermoacoustic combustion instability is one of the most challenging operational issues in
several high-performance, low-emissions combustion technologies, including gas turbines …

A weakly nonlinear analysis of the precessing vortex core oscillation in a variable swirl turbulent round jet

K Manoharan, M Frederick, S Clees… - Journal of Fluid …, 2020 - cambridge.org
We study the emergence of precessing vortex core (PVC) oscillations in a swirling jet
experiment. We vary the swirl intensity while keeping the net mass flow rate fixed using a …

The role of strain rate, local extinction, and hydrodynamic instability on transition between attached and lifted swirl flames

Q An, AM Steinberg - Combustion and Flame, 2019 - Elsevier
The coupling between fluid strain rate, local flame extinction, hydrodynamic instability, and
flame lift-off was studied in premixed swirl flames using multi-kHz repetition-rate OH …

Modelling the response of a turbulent jet flame to acoustic forcing in a linearized framework using an active flame approach

TL Kaiser, G Varillon, W Polifke, F Zhang, T Zirwes… - Combustion and …, 2023 - Elsevier
This study performs a linear mean field analysis of a turbulent reacting methane-air jet flame,
with the goal of predicting the response of the reacting flow to upstream acoustic actuation …

Experimental investigation of the helical mode in a stratified swirling flame

S Wang, J Zheng, L Xu, Q An, X Han, C Zhang, L Li… - Combustion and …, 2022 - Elsevier
In a centrally-staged combustor, the stratified swirling flame often manifests a helical mode,
which is characterized by the emergence of helical vortices, including the precessing vortex …

Complex network analysis of a premixed swirling flame influenced by precessing vortex core

Y Ren, Q Wang, Y Guan, X Xia, F Qi - Physics of Fluids, 2024 - pubs.aip.org
This work investigates the influences of precessing vortex cores (PVCs) on the coherent
interactions in the transient flow and heat release fields of a weak premixed swirling flame …

Experimental and numerical studies of the effects of the contraction ratios on the swirling flow characteristics of the model combustor outlet in lean gas turbines

MY Hashim, J Bae, J Lee - Applied Thermal Engineering, 2023 - Elsevier
Abstract Large Eddy Simulation (LES) is utilized in this work to study isothermal turbulent
swirling flow characteristics for a lean partially premixed gas turbine model combustor. The …

Impact of precessing vortex core dynamics on the thermoacoustic instabilities in a swirl-stabilized combustor

A Karmarkar, S Gupta, I Boxx… - Journal of Fluid …, 2022 - cambridge.org
Global instabilities in swirling flows can significantly alter the flame and flow dynamics of
swirl-stabilized flames, such as those in modern gas turbine engines. In this study, we …

Mean field coupling mechanisms explaining the impact of the precessing vortex core on the flame transfer function

F Lückoff, TL Kaiser, CO Paschereit… - Combustion and …, 2021 - Elsevier
The flame transfer functions (FTF) is a key quantity to assess the thermoacoustic properties
of combustion systems. It is known to depend on the hydrodynamic instabilities of the …

The effect of swirling injector geometry on the flow dynamics of precessing vortex core

J Zhu, Y Yang, Y Fang, G Wang, Y Zheng - Physics of Fluids, 2024 - pubs.aip.org
Precessing vortex core (PVC), a typical vortex structure, universally exists in swirling flow
fields and originates from the Kelvin–Helmholtz instability of the swirling shear layer. In the …