scholarly journals Flames in context of thermo-acoustic stability bounds

2015 ◽  
Vol 35 (1) ◽  
pp. 1073-1078 ◽  
Author(s):  
Maarten Hoeijmakers ◽  
Viktor Kornilov ◽  
Ines Lopez Arteaga ◽  
Philip de Goey ◽  
Henk Nijmeijer
Keyword(s):  
Acoustic Stability

Vibrational feedback control in the problem of acoustic stability

1991 ◽  
Vol 36 (4) ◽  
pp. 482-485 ◽  
Author(s):  
S. Lee ◽  
S.M. Meerkov
Keyword(s):  
Feedback Control ◽  
Acoustic Stability

Design for Thermo-Acoustic Stability: Modeling of Burner and Flame Dynamics

2013 ◽  
Author(s):  
Stefanie Bade ◽  
Michael Wagner ◽  
Christoph Hirsch ◽  
Thomas Sattelmayer ◽  
Bruno Schuermans
Keyword(s):  
Optimization Procedure ◽  
Parametric Models ◽  
Design Parameters ◽  
Model Parameters ◽  
Geometrical Parameters ◽  
Flame Dynamics ◽  
Stability Model ◽  
Flame Response ◽  
Burner Design ◽  
Acoustic Stability

A Design for Thermo-Acoustic Stability (DeTAS) procedure is presented, that aims at selecting a most stable burner geometry for a given combustor. It is based on the premise that a thermo-acoustic stability model of the combustor can be formulated and that a burner design exists, which has geometric design parameters that sufficiently influence the dynamics of the flame. Describing the flame dynamics in dependence of the geometrical parameters an optimization procedure involving a linear stability model of the target combustor maximizes the damping and thereby yields the optimal geometrical parameters. To demonstrate the procedure on an existing annular combustor a generic burner design was developed that features a significant variability of dynamical flame response in dependence of two geometrical parameters. In this paper the experimentally determined complex burner acoustics and complex flame responses are described in terms of physics based parametric models with excellent agreement between experimental and model data. It is shown that these model parameters correlate uniquely with the variation of the burner geometrical parameters, allowing to interpolate the model with respect to the geometrical parameters. The interpolation is validated with experimental data.

Numerical Analysis of the Dynamic Flame Response and Thermo-Acoustic Stability of a Full-Annular Lean Partially-Premixed Combustor

2016 ◽  
Author(s):  
Alessandro Innocenti ◽  
Antonio Andreini ◽  
Bruno Facchini ◽  
Matteo Cerutti
Keyword(s):  
Dynamic Response ◽  
Gas Turbine ◽  
Operating Conditions ◽  
System Stability ◽  
Driving Mechanism ◽  
Heavy Duty ◽  
Flame Response ◽  
Partially Premixed ◽  
Heavy Duty Gas Turbine ◽  
Acoustic Stability

A thermo-acoustic stability of a full-annular lean partially-premixed heavy-duty gas turbine combustor is carried out in the present paper. A sensitivity analysis is performed, varying the flame temperature for two operating conditions. The complex interaction between the system acoustics and the turbulent flame is studied in Ansys Fluent, using Unsteady-RANS simulations with Flamelet-Generated Manifolds combustion model. Perturbations are introduced in the system imposing a broadband excitation as inlet boundary condition. The flame response is then computed exploiting system identification techniques. The identified flame transfer functions are compared each other and the results analysed in order to give more physical insight on the coupling mechanisms responsible for the flame dynamic response. The effect of fuel mass flow fluctuations is then introduced as further driving input, describing the flame as a Multi-Input Single-Output system. Further in-depth studies are carried out on pilot flames aiming at replicating the dynamic response of the real flame and understanding the driving mechanism of thermo-acoustic instability onset as well. The obtained results are implemented into a finite element model of the combustor, realized in COMSOL Multiphysics, to analyse the system stability. Numerical model affordability has been assessed through comparisons with results from full-annular combustor experimental campaign carried out by GE Oil & Gas since the early phases of the design and development of a heavy-duty gas turbine. This allowed the discussion of the model ability to describe the stability properties of the combustor and to catch the instabilities onset as detected experimentally. Valuable indications for future design optimization were also identified thanks to the obtained results.

On some peculiarities in the operation of ground complexes when determining the acoustic stability of spacecraft construction

1998 ◽  
Vol 4 (1) ◽  
pp. 71-73
Author(s):  
V.V. Karachun ◽  
◽  
A.V. Petrik ◽  
Keyword(s):  
Acoustic Stability

scholarly journals Acoustic stability in hyrax snorts: vocal tightrope-walkers or wrathful verbal assailants?

2018 ◽  
Vol 30 (1) ◽  
pp. 223-230 ◽  
Author(s):  
Yishai A Weissman ◽  
Vlad Demartsev ◽  
Amiyaal Ilany ◽  
Adi Barocas ◽  
Einat Bar-Ziv ◽  
...  
Keyword(s):  
Acoustic Stability

Design for Thermo-Acoustic Stability: Modeling of Burner and Flame Dynamics

2013 ◽  
Vol 135 (11) ◽  
Author(s):  
S. Bade ◽  
M. Wagner ◽  
C. Hirsch ◽  
T. Sattelmayer ◽  
B. Schuermans
Keyword(s):  
Optimization Procedure ◽  
Parametric Models ◽  
Design Parameters ◽  
Model Parameters ◽  
Geometrical Parameters ◽  
Flame Dynamics ◽  
Stability Model ◽  
Flame Response ◽  
Burner Design ◽  
Acoustic Stability

A design for thermo-acoustic stability (DeTAS) procedure is presented that aims at selecting the most stable burner geometry for a given combustor. It is based on the premise that a thermo-acoustic stability model of the combustor can be formulated and that a burner design exists, which has geometric design parameters that sufficiently influence the dynamics of the flame. Describing the flame dynamics in dependence of the geometrical parameters, an optimization procedure involving a linear stability model of the target combustor, maximizes the damping and thereby yields the optimal geometrical parameters. To demonstrate the procedure on an existing annular combustor a generic burner design was developed that features significant variability of dynamical flame response in dependence of two geometrical parameters. In this paper the experimentally determined complex burner acoustics and complex flame responses are described in terms of physics-based parametric models with excellent agreement between experimental and model data. It is shown that these model parameters correlate uniquely with the variation of the burner geometrical parameters, allowing interpolating the model with respect to the geometrical parameters. The interpolation is validated with experimental data.

Combustion System Update SGT5-4000F: Design, Testing and Validation

2013 ◽  
Author(s):  
Boris F. Kock ◽  
Bernd Prade ◽  
Benjamin Witzel ◽  
Holger Streb ◽  
Mike H. Koenig
Keyword(s):  
Gas Turbines ◽  
High Reliability ◽  
Product Development Process ◽  
Test Facility ◽  
Combustion System ◽  
Lean Premixed Combustion ◽  
Air Mixing ◽  
Acoustic Stability ◽  
Combustion Tests ◽  
Cooling Air

The first Siemens AG SGT5-4000F engine with hybrid burner ring combustor (HBR) was introduced in 1996. Since then, frequent evolutionary design improvements of the combustion system were introduced to fulfill the continuously changing market requirements. The improvements particularly focused on increased thermodynamic performance, reduced emissions, and increasing operational flexibility in terms of load gradients, fuel flexibility, and turndown capability. According to the Siemens product development process, every design evolution had to pass several validation steps to ensure high reliability and best performance. The single steps included cold flow and mixing tests at atmospheric pressure, high-pressure combustion tests in full-scale sector combustion test rigs, and full engine tests at the Berlin test facility (BTF). After successful validation, the design improvements were gradually released for commercial operation. In a first step, cooling air reduction features have been implemented in 2005, followed by the introduction of a premixed pilot as second step in 2006. Both together resulted in a significant reduction of the NOx emissions of the system. In a third step, an aerodynamic burner modification was introduced in 2007, which improved the thermo-acoustic stability of the system towards higher turbine inlet temperatures and adapted to fuel preheating to allow for increased cycle efficiency. All three features together have been released as package in 2010 and to date accumulated more than 50,000 operating hours (fleet leader 24,000). This paper reports upon the steps towards this latest design status of the SGT5-4000F and presents results from typical focus areas of lean premixed combustion systems in gas turbines including aero-dynamical optimization, fuel/air mixing improvements and cooling air management in the combustor.

A modeling investigation of articulatory variability and acoustic stability during American English /r/ production

2005 ◽  
Vol 117 (5) ◽  
pp. 3196-3212 ◽  
Author(s):  
Alfonso Nieto-Castanon ◽  
Frank H. Guenther ◽  
Joseph S. Perkell ◽  
Hugh D. Curtin
Keyword(s):  
American English ◽  
Acoustic Stability
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