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Showing 1 to 9 of 9 for “"Thermo-acoustic Instabilities"”.
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Computational analysis of thermo-acoustic instabilities in combustion chambers and afterburners
A simplified model is introduced to study thermo-acoustic instabilities in asymmetric combustion chambers. Such instabilities can be triggered when correlations between heat-release and pressure oscillations exist, leading to undesirable effects. Gas turbine designs typically consist of a periodic …
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Systematic Prediction and Parametric Characterization of Thermo-Acoustic Instabilities in Premixed Gas Turbine Combustors
… the coincident prediction and observation of thermo-acoustic instabilities in a turbulent, swirl-stabilized research combustor using a stability model constructed from validated reduced-order component models. The component models included the acoustic response to flame heat release rate at …
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Application of Multi-Port Mixing for Passive Suppression of Thermo-Acoustic Instabilities in Premixed Combustors
… are commonly plagued by combustion driven instabilities. These instabilities produce large pressure and heat release rate fluctuations due to a resonant interaction between the combustor acoustics and the flame. A primary feedback mechanism responsible for driving these systems is the …
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The Design and Construction of a High Bandwidth Proportional Fuel Injection System for Liquid Fuel Active Combustion Control
… a sudden increase of interest in the control of thermo-acoustic instabilities, in particular through the use of fuel modulation techniques. The primary goal of this research was to design, construct and characterize a high bandwidth proportional fuel injection system, which could be used to study …
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A Study of the Dynamics of Laminar and Turbulent Fully and Partially Premixed Flames
… increased the likelihood of the occurrence of thermo-acoustic instabilities. The experimental techniques developed during the dynamic studies conducted on laminar flat flames were applied to swirl stabilized turbulent flames. Experiments were performed for QAir = 15 scfm and 20 scfm, F = 0.55, …
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Flame Stabilisation in the Transition to MILD Combustion
… reduction of CO and NOx pollutants, soot and thermo-acoustic instabilities compared to conventional combustion. Whilst combustion in the MILD regime offers considerable advantages over conventional combustion, neither the structure of reacting jets under MILD conditions, nor the boundaries of …
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Numerical Analysis of Flow and Heat Transfer through a Lean Premixed Swirl Stabilized Combustor Nozzle
… the resulting pressure fluctuations leading to thermo-acoustic instabilities there by creating a feedback loop with incoming reactants resulting in flow instabilities leading to flame lift off, flame extinction etc. Hence understanding combustion driven swirling flow in combustors continues to …
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A Computational Fluid Dynamics Investigation of Thermoacoustic Instabilities in Premixed Laminar and Turbulent Combustion Systems
… These combustors are often susceptible to thermo-acoustic instabilities, which manifest as pressure and heat release oscillations in the combustor. To be able to predict and control these instabilities, it is required that both the acoustics of the system, and a frequency-resolved response …
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Subharmonic and Non-Subharmonic Pulsed Control of Thermoacoustic Instabilities: Analysis and Experiment
Thermoacoustic instabilities are a problem in modern pre-mixed combustors causing reduced performance and leading in the extreme to combustor failure from excessive pressure cycles. Much work has been done using linear controllers to eliminate these instabilities. Many experimenters in the field …