..., for further uncertainty quantification (UQ) studies with modified input uncertainties. 26 06 2018 28 06 2018 Combustion Combustors Computational fluid dynamics Flame Thermoacoustics Thermoacoustic stability analysis should be an essential part of the design process of low...

... on the thermoacoustic frequencies of the combustor. We show how this communication gives rise to axial and azimuthal modes, and that these correspond to particularly synchronized states of axial thermoacoustic oscillations in each individual can. We show that these combustors typically show clusters of thermoacoustic...

... OURNAL OF E NGINEERING FOR G AS T URBINES AND P OWER . Manuscript received March 25, 2018; final manuscript received April 20, 2018; published online August 6, 2018. Editor: David Wisler. 25 03 2018 20 04 2018 Combustors Experimental Flame Modeling Thermoacoustics...

... Thermoacoustics Unsteady flows Wave propagation Flow induced noise Increased aircraft operations combined with urban densification around airports lead to the definition of more and more severe environmental regulations [ 1 ]. As the dominant noise sources for an aircraft engine, jet and fan noise...

... in a combustor where a turbulent flame acts as a thermoacoustic driver. In the proposed approach, the unfiltered pressure signal including several modes is analyzed by an algorithm based on Bayesian statistics. For this purpose, a Gibbs sampler is used to calculate parameters like damping rates...

... Gas turbine technology Thermoacoustics Turbulence Unsteady flows The multiscale nature of combustion dynamics and their coupling mechanisms makes the experimental investigation of the phenomena challenging. High thermal power density flames present in gas turbine combustors are naturally...

... 21, 2017; published online May 4, 2018. Editor: David Wisler. 16 08 2017 21 09 2017 Acoustic emission Combustion Thermoacoustics Combustion noise is at the heart of several efforts to reduce aircraft emissions. First, as large reductions in jet and fan noise have been...

... Nonintrusive diagnostics Thermoacoustics Unsteady Unsteady flows Increasingly stringent pollutant emission regulations lead aircraft engine manufacturers to move away from traditional diffusion flame based combustion systems [ 1 ]. To decrease nitrogen oxides (NO x ) emissions, lean premixed...

... of each method, validation is made with the available measured data for the pressure and vibration signals, showing that the thermoacoustic instabilities are well predicted using the CHT and two-way coupled approaches, while the zero-way interaction model prediction gives the largest discrepancy from...

...D. Ebi; A. Denisov; G. Bonciolini; E. Boujo; N. Noiray We report experimental evidence of thermoacoustic bistability in a lab-scale turbulent combustor over a well-defined range of fuel–air equivalence ratios. Pressure oscillations are characterized by an intermittent behavior with “bursts,” i.e...

...Georg A. Mensah; Luca Magri; Jonas P. Moeck Thermoacoustic instabilities are a major threat for modern gas turbines. Frequency-domain-based stability methods, such as network models and Helmholtz solvers, are common design tools because they are fast compared to compressible flow computations...

...Tobias Hummel; Frederik Berger; Nicolai Stadlmair; Bruno Schuermans; Thomas Sattelmayer This paper presents a set of methodologies for the extraction of linear growth and damping rates associated with transversal eigenmodes at screech level frequencies in thermoacoustically noncompact gas turbine...

...Vera Hoferichter; Thomas Sattelmayer Lean premixed combustion is prevailing in gas turbines to minimize nitrogen oxide emissions. However, this technology bears the risk of flame flashback and thermoacoustic instabilities. Thermoacoustic instabilities induce velocity oscillations at the burner exit...

... July 28, 2017; final manuscript received August 1, 2017; published online November 7, 2017. Editor: David Wisler. 28 07 2017 01 08 2017 Convection Flame Swirling Thermoacoustics Stricter emission regulations, in particular for nitrogen oxides (NO x ), promoted...

...Frederik M. Berger; Tobias Hummel; Bruno Schuermans; Thomas Sattelmayer This paper presents the experimental investigation of pulsation-amplitude-dependent flame dynamics associated with transverse thermoacoustic oscillations at screech level frequencies in a generic gas turbine combustor...

... dynamics Finite element methods Thermoacoustics In the near future, the air traffic is expected to increase significantly which makes a further reduction of aircraft noise indispensable. This must address all aircraft components, but particularly the engine, in order to meet strict political...

... received July 13, 2017; final manuscript received July 27, 2017; published online October 25, 2017. Editor: David Wisler. 13 07 2017 27 07 2017 Combined Combustion Combustors Computational fluid dynamics Convection Engines Flame Modeling Swirling Thermoacoustics Unsteady...

...] Campa , G. , and Camporeale , S. M. , 2014 , “ Prediction of the Thermoacoustic Combustion Instabilities in Practical Annular Combustors ,” ASME J. Eng. Gas Turbines Power , 136 ( 9 ), p. 091504 . 10.1115/1.4027067 [4] Bauerheim , M. , Parmentier , J.-F. , Salas , P...

... July 26, 2017; published online October 17, 2017. Editor: David Wisler. 06 07 2017 26 07 2017 Combustion Combustors Experimental Flame Thermoacoustics Lean-premixed gas turbines used for power generation purposes are prone to combustion instabilities caused...

... (SPOD). The results show that the transitions are governed by two types of instability, namely a hydrodynamic instability in the form of a precessing vortex core (PVC) and a thermoacoustic (TA) instability. The LSA shows that the V-M transition implies the transient formation of a PVC as the result...