Thermo-acoustic velocity coupling in a swirl stabilized gas turbine model combustor

Abstract

ii Acknowledgements The fact that the cover page of this thesis reads Vincent R. Caux-Brisebois is a misleading proposition that the content of this work is the product of a single man's endeavour.Although nothing would please me more than adding the names of all those who made this possible, the imposed front-to-back limit of 100 pages would hardly allow the table of contents to be published. Nevertheless, I will try to show my appreciation to all those who made this possible in the short space that is available to me.The second name that would go on the cover page of this document is without doubt Prof. Adam M. Steinberg's. In fact, if the degree of MASc. were not conditional to this dissertation, I would likely insist that it be written above mine. Prof. Steinberg is one of the few supervisors that I have known to always work with his door wide open. At any time during his long working hours, any student can walk in and ask any question knowing he or she will be well received, treated fairly, and perhaps most importantly, get the help they need. The work presented in this thesis would not have been possible without his valuable input, guidance, and hard work. Though I could go on about why Prof. Steinberg is a model supervisor, I have to cut this discussion short for the sake of space, and take this opportunity to thank the second reader of this dissertation, Prof. C. P. T. Groth, for taking some time out of his already-full schedule to review this work.

Experimental analysis of thermo-acoustic instabilities in a generic gas turbine combustor by phase-correlated PIV, chemiluminescence, and laser Raman scattering measurements

“…This is, however, not the only quantity that determines the heat release rate and its cyclic variations. Fluctuations in the flame surface area can be induced by periodic variations of the flow field, as was found in perfectly premixed configurations [Balachandran 2005, Caux-Brisebois 2014. Although the fuel consumption remains the decisive quantity, phasedependent characteristics of the flow field can trigger local changes in the fuel consumption rate.…”

“…In addition, understanding and predicting combustor thermo-acoustic behavior is complicated by significant effects of turbulence-chemistry interaction , Gicqel 2012, Lückerath 2011, Rebosio 2010, and spatially and temporally varying degrees of premixing [Bade 2014, Masri 2015, Stopper 2013. The occurrence of hydrodynamic instabilities like precessing vortex cores, vortex shedding, or other shear layer instabilities [Candel 2014, Caux-Brisebois 2014, Kim 2014, Moeck 2012, Stöhr 2013b further complicates the situation. For example, precessing vortex cores can influence the mixing , or can cause flame role-up and local extinction [Stöhr2013a].…”

“…Those measurements include OH* and CH* chemiluminescence to identify heat release variations, OH, CH 2 O and CH PLIF to determine fluctuations in the flame surface density or local Rayleigh index and laser Raman measurements to assess changes in the thermo-chemical state of the flame [Bellows 2007, Biagioli 2008, Giezendanner 2003, Hubschmid 2008, Ishino 2001, Lee 2003, Schildmacher 2006. More recently, high-speed imaging techniques in combination with acoustic pressure tracing have been applied to study thermo-acoustic instabilities in GT-relevant combustors , Caux-Brisebois 2014, Durox 2013, Galley 2011, Gounder 2014, Steinberg 2010, Steinberg 2012, Steinberg 2013, Worth 2012, yielding deeper insight into the feedback mechanisms.…”

Development and evaluation of gappy-POD as a data reconstruction technique for noisy PIV measurements in gas turbine combustors

“…The combustor has been the subject of numerous previous studies (e.g. Meier et al (2007); Franzelli et al (2012); Dem et al (2015); Oberleithner et al (2015)) wherein the geometry is discussed in detail, and the data used here were previously described by Steinberg et al (2013) and Caux-Brisebois et al (2014). To summarize, 10 kHz stereoscopic PIV (S-PIV) vector fields were computed using the LaVision DaVis 8.0 software package, with a final interrogation box size and vector spacing of approximately 1.0 mm and 0.5 mm respectively, and a total number of 7870 snapshots per data set.…”

“…Particle image velocimetry (PIV) is the de facto standard 2D velocity measurement technique in GTC-relevant flows (e.g. Fureby et al (2007) ;Stopper et al (2013); Temme et al (2014); Arndt et al (2015); Boxx et al (2015); Cosic et al (2015); Caux-Brisebois et al (2014)). However, multi-kHz PIV measurements from diode-pumped solidstate lasers typically generate relatively low signal compared to conventional pulsed lasers, while highpressure liquid-fueled combustion generates high background luminosity from flame chemiluminescence and soot.…”