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Actively passive control of thermoacoustic instability
The Journal of the Acoustical Society of America, 2017In this work, experimental studies of actively passive control of perforated liner with a bias flow on mitigating thermoacoustic instability are performed. For this, a well-designed Rijke-type thermoacoustic combustor with a perforated liner implemented is designed. A premixed propane-fueled flame is confined in the bottom half.
Dan Zhao, Ashique Akram Tarique, Shen Li
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Thermoacoustic Instability in a Rijke Tube: Non-Normality and Nonlinearity
13th AIAA/CEAS Aeroacoustics Conference (28th AIAA Aeroacoustics Conference), 2007The role of non-normality and nonlinearity in thermoacoustic interaction in a Rijke tube is investigated in this paper. The heat release rate of the heating element is modeled by a modified form of King’s law. This fluctuating heat release from the heating element is treated as a compact source in the one-dimensional linear model of the acoustic field.
Balasubramanian, Koushik, Sujith, R. I.
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Intrinsic thermoacoustic instability of premixed flames
Combustion and Flame, 2015Abstract The thermoacoustic stability of velocity sensitive premixed flames is investigated. A causal representation of the flow-flame-acoustic interactions reveals a flame-intrinsic feedback mechanism. The feedback loop may be described as follows: An upstream velocity disturbance induces a modulation of the heat release rate, which in turn ...
Thomas Emmert +2 more
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Thermoacoustic Flow Instability in a Scramjet Combustor
41st AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, 2005*† ‡ § ¶ This paper deals with the thermoacoustic instability and ensuing flow oscillation in a scramjet engine, a phenomenon commonly known as combustion instability. The analysis is based on a quasi-one-dimensional treatment of unsteady flow motion, which simulates the main features of the oscillatory flowfields in both the isolator and combustor ...
Fuhua Ma +4 more
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Impact of Linear Coupling on Thermoacoustic Instabilities
Combustion Science and Technology, 2008There have been conflicting opinions in literature, about the consequences of ignoring the linear coupling terms in finite-dimensional thermoacoustic models. We try to clarify this issue in this paper. We study consequences of ignoring the linear coupling terms on the non-normal thermoacoustic interactions in a horizontal Rijke tube.
K. S. Kedia +2 more
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Subcritical thermoacoustic instabilities in a premixed combustor
14th AIAA/CEAS Aeroacoustics Conference (29th AIAA Aeroacoustics Conference), 2008Subcritical thermoacoustic instabilities are investigated in a premixed combustor test rig with a swirl-stabilized burner. Triggering of limit cycle oscillations from initially stable states as well as hysteresis in the variation of the preheat temperature and the air and gas mass flows is found. The stable fixed point and the stable limit cycle in the
Jonas Moeck +4 more
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Linear thermoacoustic instability in the time domain
The Journal of the Acoustical Society of America, 1998An approximate time-domain description of the development of the thermoacoustic instability in gas-filled tubes is developed by exploiting the difference between the instability time scale and the period of standing waves. The perturbation results compare very favorably with the exact frequency-domain theory of Rott.
S. Karpov, A. Prosperetti
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Intermittency: A State that Precedes Thermoacoustic Instability
2017Thermoacoustic instability is a plaguing problem in confined combustion systems, where self-sustained periodic oscillations of ruinous amplitudes that cause serious damage and performance loss to propulsive and power generating systems occur. In this chapter, we review the recent developments in understanding the transition route to thermoacoustic ...
Samadhan A. Pawar, R. I. Sujith
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Modeling, Analysis, and Control of Thermoacoustic Instabilities
2010Moderne Gasturbinen werden mit magerer Vormischverbrennung betrieben, um niedrige Emissionsstandards zu erfüllen. Diese Art der Verbrennung ist jedoch äußerst anfällig gegenüber Störungen der Flamme durch akustische Schwankungen. Hierdurch entstehen sogenannte thermoakustische Instabilitäten, die sich durch außerordentlich hohe Druckpulsationen ...
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