Results 271 to 280 of about 633,794 (335)

Linear time-continuous state-space realization of flame transfer functions by means of a propagation equation.

INTER-NOISE and NOISE-CON Congress and Conference Proceedings, 2023
Low-order network models, commonly used to assess the thermo-acoustic stability of combustors, can be cast in a linear, time-continuous state-space representation.
P. Brokof, Guillaume J. J. Fournier, W. Polifke   +2 more
semanticscholar   +1 more source

Flame Transfer Function Calculations for Combustion Oscillations

Volume 2: Coal, Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations, 2001
Combustors with fuel-spray atomisers are particularly susceptible to a low-frequency oscillation at idle and sub-idle conditions. For aero-engine combustors, the frequency of this oscillation is typically in the range 50-120Hz and is commonly called ‘rumble’.
M. Zhu, A. P. Dowling, K. N. C. Bray
openaire   +1 more source

Modeling of premixed swirling flames transfer functions

Proceedings of the Combustion Institute, 2011
Abstract An analytical model is derived for the linear response of swirling flames submitted to velocity disturbances. The flame dynamics is represented by a linearized version of the G-equation. Turbulent fluctuations are first averaged in time to obtain a kinematic equation in which the flame is represented by a wrinkled sheet.
Paliès, P., Durox, D., Schuller, Thierry, Candel, S.   +3 more
openaire   +2 more sources

Experimental analysis of nonlinear flame transfer functions for different flame geometries

Proceedings of the Combustion Institute, 2009
Abstract Nonlinear features of flame dynamics are characterized by measuring the flame transfer functions for different input levels. This provides a family of gain and phase curves, which constitute the Flame Describing Functions (FDF) and can be used to analyze self-sustained combustion oscillations.
D. Durox, T. Schuller, N. Noiray, S. Candel   +3 more
openaire   +1 more source

Flame Transfer Function Characteristics of Swirl Flames for Gas Turbine Applications

Volume 2: Turbo Expo 2003, 2003
For the suppression or reduction of self-sustained combustion instabilities, modifications of the burner outlet conditions, that strongly influence the dynamic flame response, seem to be the most promising way. Therefore, to derive a detailed physical understanding of the feedback mechanisms the dynamic flame response characteristics, quantified by ...
Martin Lohrmann, Horst Bu¨chner, Nikolaos Zarzalis, Werner Krebs   +3 more
openaire   +1 more source

From Pressure Time Series Data to Flame Transfer Functions: A Framework for Perfectly-Premixed Swirling Flames

Journal of Engineering For Gas Turbines and Power, 2022
We present a two-step optimization (TSO) framework, which uses the pressure data of an unstable combustion process to estimate the Flame Transfer Function (FTF).
A. Ghani, Alp Albayrak
semanticscholar   +1 more source

Validation of Flame Transfer Function Reconstruction for Perfectly Premixed Swirl Flames

Volume 1: Turbo Expo 2004, 2004
The introduction of lean premix combustion increases the susceptibility of the combustor to thermoacoustic instabilities. To control these instabilities, information about the dynamic behavior of the combustion process is necessary. The flame transfer function offers one possibility to describe the dynamic behavior of the combustion process. It relates
A. Gentemann, C. Hirsch, K. Kunze, F. Kiesewetter, T. Sattelmayer, W. Polifke   +5 more
openaire   +1 more source

Quantification of the Impact of Uncertainties in Operating Conditions on the Flame Transfer Function With Nonintrusive Polynomial Chaos Expansion

Journal of Engineering For Gas Turbines and Power, 2018
Nonintrusive polynomial chaos expansion (NIPCE) is used to quantify the impact of uncertainties in operating conditions on the flame transfer function (FTF) of a premixed laminar flame.
A. Avdonin, W. Polifke
semanticscholar   +1 more source

URANS-Modelling of Flame Transfer Functions of Turbulent Premixed Jet Flames

Volume 1: Turbo Expo 2004, 2004
The understanding of the formation of self excited pressure oscillations in technical combustion systems depends on the knowledge of the dynamical behaviour of the flame used. As an important mechanism driving these combustion instabilities the formation and reaction of coherent large-scale ring-vortices has been indentified.
Matthias Hettel, Peter Habisreuther, Horst Bu¨chner, Henning Bockhorn, Nikolaos Zarzalis   +4 more
openaire   +1 more source

Pressure Influence on the Flame Transfer Function of a Premixed Swirling Flame

Volume 1: Combustion and Fuels, Education, 2006
In order to assess the stability of gas turbine combustors measured flame transfer functions are frequently used in thermoacoustic network models. Although many combustion systems operate at high pressure, the measurement of flame transfer functions was essentially limited to atmospheric conditions in the past.
E. Freitag, H. Konle, M. Lauer, C. Hirsch, T. Sattelmayer   +4 more
openaire   +1 more source