Intrinsic thermoacoustic instabilities

CF Silva - Progress in Energy and Combustion Science, 2023 - Elsevier
It is accepted that the thermoacoustic behavior of a given combustion system can be
analyzed by investigating how its natural acoustic modes are perturbed by the flame …

Modeling and analysis of premixed flame dynamics by means of distributed time delays

W Polifke - Progress in Energy and Combustion Science, 2020 - Elsevier
The unsteady response of a flame to acoustic or flow perturbations plays a crucial role in
thermoacoustic combustion instability. The majority of studies on this subject presents and …

Adjoint methods as design tools in thermoacoustics

L Magri - Applied Mechanics Reviews, 2019 - asmedigitalcollection.asme.org
In a thermoacoustic system, such as a flame in a combustor, heat release oscillations couple
with acoustic pressure oscillations. If the heat release is sufficiently in phase with the …

Acoustic and intrinsic thermoacoustic modes of a premixed combustor

T Emmert, S Bomberg, S Jaensch, W Polifke - Proceedings of the …, 2017 - Elsevier
Premixed flames are velocity sensitive, ie, they react to a velocity perturbation at the burner
mouth, say, with fluctuations in heat release rate. Unsteady heat release generates acoustic …

Control of intrinsic thermoacoustic instabilities using hydrogen fuel

A Ghani, W Polifke - Proceedings of the Combustion Institute, 2021 - Elsevier
This conceptual numerical study explores a possible strategy for control of unstable intrinsic
thermoacoustic (ITA) modes. Control of the ITA feedback loop has not been discussed yet …

sss & sssMOR: Analysis and reduction of large-scale dynamic systems in MATLAB

A Castagnotto, MC Varona, L Jeschek… - at …, 2017 - degruyter.com
We present two MATLAB toolboxes, provided as open-source code, that expand the
capabilities of the Control System Toolbox to large-scale models. sss allows the definition …

On the spurious entropy generation encountered in hybrid linear thermoacoustic models

M Meindl, CF Silva, W Polifke - Combustion and Flame, 2021 - Elsevier
This work demonstrates that a hybrid approach for linear thermoacoustic stability analysis
that combines the Linearized Navier–Stokes Equations (LNSE) with a global Flame Transfer …

Thermoacoustic analysis of a laminar premixed flame using a linearized reactive flow solver

A Avdonin, M Meindl, W Polifke - Proceedings of the Combustion Institute, 2019 - Elsevier
In this paper, the dynamics and thermoacoustic stability of a laminar premixed flame are
analyzed using a linearized reactive flow (LRF) solver. The LRF solver is based on …

Intrinsic thermoacoustic feedback loop in turbulent spray flames

A Ghani, T Steinbacher, A Albayrak, W Polifke - Combustion and Flame, 2019 - Elsevier
This paper investigates low-frequency thermoacoustic instabilities of a turbulent spray flame,
a phenomenon known as 'rumble'. Based on experimental data, a network model analysis is …

Hybrid CFD/low-order modeling of nonlinear thermoacoustic oscillations

S Jaensch, M Merk, EA Gopalakrishnan… - Proceedings of the …, 2017 - Elsevier
This paper proposes and compares two nonlinear time-domain models of self-excited
thermoacoustic oscillations of laminar premixed flames. Both models are hybrid …