Nonorthogonality analysis of a thermoacoustic system with a premixed V-shaped flame

Transient growth of acoustical energy associated with mitigating thermoacoustic oscillations

“…To gain insight on the finite-time (transient) stability behaviors, transient growth analysis of acoustical energy in a thermoacoustic system receives more attention recently [16][17][18]. A choked thermoacoustic combustor is studied to gain insight on its nonnormality.…”

“…It is found that the maximum transient growth can be 10 3 times greater than the initial disturbances energy. Experimental measurement of the transient growth was conducted on a premixed gas turbine combustor [15] mean valuê approximation value [16][17][18]. However, most of thermoacoustics systems studied previously are open-ended one, of which pressure nodes are expected at both inlet and outlet [3].…”

“…Thus it is important to gain insight on the onset of thermoacoustic instability [12,13,2] and to develop mitigation/-control approaches. Over last few decades, thermoacoustic instability has been intensively studied [14][15][16][17][18][19][20]. Generally, linear modal analysis is conducted via calculating the eigenfrequencies of thermoacoustic systems [3].…”

Theoretical and experimental investigation of thermoacoustics transfer function

“…These oscillations are mainly caused by the http://dx.doi.org/10.1016/j.apenergy.2015.04.026 0306-2619/Ó 2015 Elsevier Ltd. All rights reserved. energy transferred from the heat source to sound waves [10][11][12][13][14][15][16][17], which depends upon the nature of coupling between the flame and oncoming flow fluctuations [18,19]. Small amplitude flow disturbances can excite natural modes of combustion chamber and cause them to grow into a nonlinear limit cycle.…”

System Identification and Resonant Control of Thermoacoustic Engines for Robust Solar Power

“…To such a situation, suppressing mean-flow buckling but keeping thermoacoustic instability is a remedy. The control of mean-flow buckling was usually through passive approaches, such as re-shaping the chambers [11][12][13][14], changing the working gas [15], re-designing the heat regeneration [16][17][18][19][20][21][22], etc., based on the analysis of computation fluid dynamics as in [11,23,24] for example. As indicated in the literature of combustion instabilities [25][26][27][28], suppression of mean-flow buckling is usually accompanied by reduction of acoustic motions.…”