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Georgia Tech
1.
Gao, Xiang.
The effects of ozone addition on flame propagation and stabilization.
Degree: PhD, Aerospace Engineering, 2017, Georgia Tech
URL: http://hdl.handle.net/1853/59251
► Combustion plays a vital role in transportation and power generation. However, concerns of efficiency, emission, and operations at extreme conditions highlight the needs to enhance…
(more)
▼ Combustion plays a vital role in transportation and power generation. However, concerns of efficiency, emission, and operations at extreme conditions highlight the needs to enhance combustion process. If the rate-limiting chemical pathways can be modified, the ignition and combustion process could be dramatically accelerated. Following this idea, addition of ozone (O3) is proposed as a potential solution. O3 is one of the strongest oxidizers. It can be efficiently and economically produced in situ at high pressures, and transported to the desired region from an injection location to modify fuel oxidization and control the combustion process.
To serve as a basis for future application on practical combustion systems, this dissertation investigates the effects of O3 addition on two fundamental combustion processes: the propagation of laminar premixed flames and the
stabilization of non- premixed jet flames in autoignitive environment. Previous studies have shown that O3 addition can enhance
flame propagation, stability and ignition, but the dependence on pressure and temperature were not clear. Furthermore, few studies have been conducted on the effects of ozonolysis reactions, which are rapid even at room temperature for unsaturated hydrocarbons. The results presented in this dissertation are an attempt to address these questions.
The effects of O3 addition on the propagation of laminar premixed flames are investigated with respect to pressure, initial temperature, O3 concentration and fuel kinetics. For alkane/air premixed laminar flames, high-pressure Bunsen
flame experiments in the present work show that the enhancement in laminar
flame speed (SL) increases with pressures. This is due to the fact that O3 decomposition, which releases reactive oxygen atoms, becomes a more dominant O3 consumption pathway at higher pressure. Simulations show that adding O3 at higher initial temperature is not as effective as lower initial temperatures. A nearly linear relation between the enhancement and O3 concentration is observed at room temperature and atmospheric pressure. If the fuel is changed from alkanes to C2H4, an unsaturated hydrocarbon species, ozonolysis reactions take place in the premixing process. When the heat released from ozonolysis reactions is lost, decrease in SL is observed. In contrast, if ozonolysis reaction are frozen, either by cooling the reactants or decreasing the pressure, enhancement of SL by O3 addition is observed.
The study on
flame stabilization with O3 addition is conducted with a non-premixed jet burner in a quartz tube using C2H4 as the fuel. At low-dilution conditions, autoignition events are initiated by ozonolysis reactions. The autoignition timescale is further investigated quantitatively. Overall, this timescale decreases as the inlet velocity increases. At such autoignitive conditions created by ozonolysis reactions, the
stabilization of a lifted non-premixed
flame is fundamentally different from non-autoignitive conditions. Propagation is enhanced due to the “preprocessing” of fuel by…
Advisors/Committee Members: Sun, Wenting (advisor), Ombrello, Timothy (committee member), Seitzman, Jerry (committee member), Sankar, Lakshmi (committee member), Jagoda, Jechiel (committee member).
Subjects/Keywords: Ozone; Flame propagation; Flame stabilization; Ozonolysis
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APA (6th Edition):
Gao, X. (2017). The effects of ozone addition on flame propagation and stabilization. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/59251
Chicago Manual of Style (16th Edition):
Gao, Xiang. “The effects of ozone addition on flame propagation and stabilization.” 2017. Doctoral Dissertation, Georgia Tech. Accessed January 25, 2021.
http://hdl.handle.net/1853/59251.
MLA Handbook (7th Edition):
Gao, Xiang. “The effects of ozone addition on flame propagation and stabilization.” 2017. Web. 25 Jan 2021.
Vancouver:
Gao X. The effects of ozone addition on flame propagation and stabilization. [Internet] [Doctoral dissertation]. Georgia Tech; 2017. [cited 2021 Jan 25].
Available from: http://hdl.handle.net/1853/59251.
Council of Science Editors:
Gao X. The effects of ozone addition on flame propagation and stabilization. [Doctoral Dissertation]. Georgia Tech; 2017. Available from: http://hdl.handle.net/1853/59251

University of Iowa
2.
Kaufman, Kelsey Leigh.
Effect of hydrogen addition and burner diameter on the stability and structure of lean, premixed flames.
Degree: MS, Mechanical Engineering, 2014, University of Iowa
URL: https://ir.uiowa.edu/etd/4661
► Low swirl burners (LSBs) have gained popularity in heating and gas power generation industries, in part due to their proven capacity for reducing the…
(more)
▼ Low swirl burners (LSBs) have gained popularity in heating and gas power generation industries, in part due to their proven capacity for reducing the production of NOx, which in addition to reacting to form smog and acid rain, plays a central role in the formation of the tropospheric ozone layer. With lean operating conditions, LSBs are susceptible to combustion instability, which can result in
flame extinction or equipment failure. Extensive work has been performed to understand the nature of LSB combustion, but scaling trends between laboratory- and industrial-sized burners have not been established. Using hydrogen addition as the primary method of
flame stabilization, the current work presents results for a 2.54 cm LSB to investigate potential effects of burner outlet diameter on the nature of
flame stability, with focus on flashback and lean blowout conditions. In the lean regime, the onset of instability and
flame extinction have been shown to occur at similar equivalence ratios for both the 2.54 cm and a 3.81 cm LSB and depend on the resolution of equivalence ratios incremented. Investigations into
flame structures are also performed. Discussion begins with a derivation for properties in a multicomponent gas mixture used to determine the Reynolds number (Re) to develop a condition for turbulent intensity similarity in differently-sized LSBs. Based on this requirement, operating conditions are chosen such that the global Reynolds number for the 2.54 cm LSB is within 2% of the Re for the 3.81 cm burner. With similarity obtained,
flame structure investigations focus on
flame front curvature and
flame surface density (FSD). As
flame structure results of the current 2.54 cm LSB work are compared to results for the 3.81 cm LSB, no apparent relationship is shown to exist between burner diameter and the distribution of
flame surface density. However, burner diameter is shown to have a definite effect on the
flame front curvature. In corresponding flow conditions, a decrease in burner diameter results a broader distribution of curvature and an increased average curvature, signifying that compared to the larger 3.81 cm LSB, the
flame front of the smaller burner contains tighter, smaller scale wrinkling.
Advisors/Committee Members: Ratner, Albert (supervisor).
Subjects/Keywords: Combustion Instability; Flame Stabilization; Flame Structures; Lean; Premixed Combustion; Low Swirl Burner; NOx; Mechanical Engineering
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
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APA (6th Edition):
Kaufman, K. L. (2014). Effect of hydrogen addition and burner diameter on the stability and structure of lean, premixed flames. (Masters Thesis). University of Iowa. Retrieved from https://ir.uiowa.edu/etd/4661
Chicago Manual of Style (16th Edition):
Kaufman, Kelsey Leigh. “Effect of hydrogen addition and burner diameter on the stability and structure of lean, premixed flames.” 2014. Masters Thesis, University of Iowa. Accessed January 25, 2021.
https://ir.uiowa.edu/etd/4661.
MLA Handbook (7th Edition):
Kaufman, Kelsey Leigh. “Effect of hydrogen addition and burner diameter on the stability and structure of lean, premixed flames.” 2014. Web. 25 Jan 2021.
Vancouver:
Kaufman KL. Effect of hydrogen addition and burner diameter on the stability and structure of lean, premixed flames. [Internet] [Masters thesis]. University of Iowa; 2014. [cited 2021 Jan 25].
Available from: https://ir.uiowa.edu/etd/4661.
Council of Science Editors:
Kaufman KL. Effect of hydrogen addition and burner diameter on the stability and structure of lean, premixed flames. [Masters Thesis]. University of Iowa; 2014. Available from: https://ir.uiowa.edu/etd/4661

North Carolina State University
3.
McCraw, Jennifer Leigh.
Observations on Upstream Flame Propagation in Ignited Hydrocarbon Jets.
Degree: MS, Mechanical Engineering, 2006, North Carolina State University
URL: http://www.lib.ncsu.edu/resolver/1840.16/318
► Studies are presented that examine the development of combustion in an initially non-reacting methane jet after ignition at a downstream location. Image measurements depicting the…
(more)
▼ Studies are presented that examine the development of combustion in an initially non-reacting methane jet after ignition at a downstream location. Image measurements depicting the axial location of a fixed energy ignition source that permits transient
flame propagation back to the nozzle are presented. The results from the experimental investigations are discussed. Nine different cases were investigated in order to determine the major parameters that impact the axial location of the ignition source at which
flame propagation back to the burner was permitted. When the ignition source was located at larger axial distances than those indicated,
flame propagation upstream to the burner was not possible and, instead, the
flame blew out. The Reynolds number of the jet, the scalar field and the air co-flow magnitude were investigated for their contributions. A standard digital video camera was used in order to film the ignition of the jet and to determine the farthest axial location from the burner at which upstream
flame propagation was possible. With the aid of computer software, the height for each case was determined. Conclusions to the effect these parameters had on the axial location are discussed as well as the implications for the physics governing the process.
Advisors/Committee Members: Dr. Kevin Lyons, Committee Chair (advisor), Dr. James Leach, Committee Member (advisor), Dr. Eric Klang, Committee Member (advisor).
Subjects/Keywords: Combustion; Premixed Flame; Flame Propagation; Flame Stabilization
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
McCraw, J. L. (2006). Observations on Upstream Flame Propagation in Ignited Hydrocarbon Jets. (Thesis). North Carolina State University. Retrieved from http://www.lib.ncsu.edu/resolver/1840.16/318
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
McCraw, Jennifer Leigh. “Observations on Upstream Flame Propagation in Ignited Hydrocarbon Jets.” 2006. Thesis, North Carolina State University. Accessed January 25, 2021.
http://www.lib.ncsu.edu/resolver/1840.16/318.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
McCraw, Jennifer Leigh. “Observations on Upstream Flame Propagation in Ignited Hydrocarbon Jets.” 2006. Web. 25 Jan 2021.
Vancouver:
McCraw JL. Observations on Upstream Flame Propagation in Ignited Hydrocarbon Jets. [Internet] [Thesis]. North Carolina State University; 2006. [cited 2021 Jan 25].
Available from: http://www.lib.ncsu.edu/resolver/1840.16/318.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
McCraw JL. Observations on Upstream Flame Propagation in Ignited Hydrocarbon Jets. [Thesis]. North Carolina State University; 2006. Available from: http://www.lib.ncsu.edu/resolver/1840.16/318
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
4.
Τσιρώνης, Γεώργιος.
Μελέτη συμπεριφοράς φλογών προπανίου σταθεροποιημένων σε επίπεδο σώμα με διαστρωματωμένη εισαγωγή μίγματος.
Degree: 2014, University of Patras
URL: http://hdl.handle.net/10889/8112
► Στην παρούσα διπλωματική εργασία παρουσιάζονται και συζητούνται τα χαρακτηριστικά τυρβωδών φλογών μερικής προανάμιξης. Οι φλόγες που εξετάζονται προέρχονται από ένα επίπεδο καυστήρα-σταθεροποιητή ορθογωνικής διατομής, δύο…
(more)
▼ Στην παρούσα διπλωματική εργασία παρουσιάζονται και συζητούνται τα χαρακτηριστικά τυρβωδών φλογών μερικής προανάμιξης. Οι φλόγες που εξετάζονται προέρχονται από ένα επίπεδο καυστήρα-σταθεροποιητή ορθογωνικής διατομής, δύο επάλληλων κοιλοτήτων, που σχηματίζονται κατά μήκος τριών παραλλήλων επιπέδων. Οι φλόγες σταθεροποιούνται στην ανακυκλοφορία των καπναερίων που δημιουργείτε κατάντη του φλογοσταθεροποιητή.
Στόχος της έρευνας ήταν να διερευνηθεί η συγκεκριμένη διάταξη ως προς το θερμοκρασιακό της πεδίο και την σταθεροποίηση της συγκεκριμένης φλόγας που προκαλεί η καύση της βαθμιαίας διαστρωμάτωσης προπανίου- αέρα.
Για να επιτευχθεί ο στόχος αυτός πραγματοποιήθηκαν διαφορετικά είδη μετρήσεων σε διαφορετικές παροχές καυσίμου και καταγράφηκαν τα αποτελέσματα, τα οποία στη συνέχεια συγκρίθηκαν και με διερευνήσεις που πήραμε από ειδικευμένο υπολογιστικό πρόγραμμα υπό τις ίδιες οριακές συνθήκες.
Τέλος, μετά τη σύγκριση των αποτελεσμάτων μεταξύ πειράματος και προσομοίωσης έγινε προσπάθεια να εξηγηθούν οι διαφορές που παρατηρήθηκαν και τα χαρακτηριστικά δομικά στοιχεία που συντέλεσαν στην περιγραφή της λειτουργικής συμπεριφοράς των χρησιμοποιηθέντων στρωματοποιημένων φλογών ώστε να δοθούν ιδέες για την περαιτέρω εξέλιξη της έρευνας.
In this study the characteristics of partially premixed turbulent flames are presented and discussed. The investigated flames come from a planar stabilization burner of two superimposed cavities formed along three parallel planes. The flames are stabilized within the downstream vortex region of the afterbody.
The aim of this study was to investigate the specific experimental arrangement as for the temperature field and the stabilization of these stratified propane- air flames.
To achieve this goal different types of measurements have been made at different fuel supplies and the results have been recorded and compared with computational investigations which have been carried out using a specialized commercial simulation package under the same boundary conditions.
Finally, after comparing the experimental and computational results effort has been made to explain the differences observed and the characteristic structural elements that contributed to the description of the functional behavior of stratified flames in order to provide ideas for further investigation.
Advisors/Committee Members: Κούτμος, Παναγιώτης, Tsironis, George, Λευθεριώτης, Γεώργιος, Αργυρίου, Αθανάσιος, Τρυπαναγνωστόπουλος, Ιωάννης.
Subjects/Keywords: Καύση; Σταθεροποίηση φλογών; Μερικώς προαναμεμιγμένες φλόγες; 621.402 3; Burning; Flame stabilization
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Τσιρώνης, . (2014). Μελέτη συμπεριφοράς φλογών προπανίου σταθεροποιημένων σε επίπεδο σώμα με διαστρωματωμένη εισαγωγή μίγματος. (Masters Thesis). University of Patras. Retrieved from http://hdl.handle.net/10889/8112
Chicago Manual of Style (16th Edition):
Τσιρώνης, Γεώργιος. “Μελέτη συμπεριφοράς φλογών προπανίου σταθεροποιημένων σε επίπεδο σώμα με διαστρωματωμένη εισαγωγή μίγματος.” 2014. Masters Thesis, University of Patras. Accessed January 25, 2021.
http://hdl.handle.net/10889/8112.
MLA Handbook (7th Edition):
Τσιρώνης, Γεώργιος. “Μελέτη συμπεριφοράς φλογών προπανίου σταθεροποιημένων σε επίπεδο σώμα με διαστρωματωμένη εισαγωγή μίγματος.” 2014. Web. 25 Jan 2021.
Vancouver:
Τσιρώνης . Μελέτη συμπεριφοράς φλογών προπανίου σταθεροποιημένων σε επίπεδο σώμα με διαστρωματωμένη εισαγωγή μίγματος. [Internet] [Masters thesis]. University of Patras; 2014. [cited 2021 Jan 25].
Available from: http://hdl.handle.net/10889/8112.
Council of Science Editors:
Τσιρώνης . Μελέτη συμπεριφοράς φλογών προπανίου σταθεροποιημένων σε επίπεδο σώμα με διαστρωματωμένη εισαγωγή μίγματος. [Masters Thesis]. University of Patras; 2014. Available from: http://hdl.handle.net/10889/8112

University of Illinois – Chicago
5.
Badhe, Abhijeet Sanjay.
Flame Stabilization and Lean Blowout Prediction by LES Combustion Model with Strain and Heat Loss Effects.
Degree: 2017, University of Illinois – Chicago
URL: http://hdl.handle.net/10027/22216
► Modern ultra-low NOx combustors in land based gas turbines operate mostly in lean premixed mode, close to their lean limits making the flame susceptible to…
(more)
▼ Modern ultra-low NOx combustors in land based gas turbines operate mostly in lean premixed mode, close to their lean limits making the
flame susceptible to instabilities and blow out. There is significant interest in examining and predicting the lean blowout conditions using CFD and other computational tools, which have now become an integral part of combustor design and development process. However, very limited literature is currently available on the CFD prediction of lean blowout (LBO) of turbulent premixed flames. Experimental studies of LBO phenomenon reveal that
flame stretch induced local extinction is the primary precursor to blowout. Turbulent
Flame Speed Closure model with Strain and Heat Loss Effects (TFC-SHL), and without these effects i.e. the Standard TFC model (STFC), have been employed in LES framework for this computational study. These two models have been evaluated for their capabilities to correctly predict
stabilization and blowout of turbulent lean premixed flames. Recognizing that heat loss enhances sensitivity of
flame to strain, combined influence of strain and heat loss was thus anticipated to capture the local extinction events and eventually the
flame blowout. A simple lab-scale, conical bluff-body combustor configuration from University of Cambridge was selected for computing lean premixed methane-air flames. LBO was approached by reducing the mixture equivalence ratio. LES simulations were performed in ANSYS Fluent 17.0, wherein, a user defined function (UDF) implementing the TFC-SHL model was used. Simulation results were validated against available OH-PLIF and OH* Chemiluminescence experimental data. The Extended TFC model, predicts experimentally observed changes in
flame structure, as it approaches blowout with increasingly lean mixtures. and many important aspects of blowout dynamics. On the contrary, the STFC model, gives flawed results with incorrect
flame structure and the
flame burning strongly at blowout condition. While Standard TFC (STFC) is unable to predict
flame extinction, Extended TFC (TFC-SHL) can capture extinction at the experimentally determined blowout point. Improvements in predictive capability of Extended model can be attributed to the inclusion of strain and heat loss effects. This study in general also emphasize that enhancing physics in combustion models can significantly improve CFD predictions of important phenomenon in combustion.
Advisors/Committee Members: Aggarwal, Suresh K. (advisor), Mashayek, Farzad (committee member), Paoli, Roberto (committee member), Aggarwal, Suresh K (chair).
Subjects/Keywords: Lean blowout (LBO); gas turbines; turbulent premixed combustion; bluff-body; flame stabilization; flame extinction, LES, flame stretch, hydrodynamic strain, heat loss, turbulent flame speed.
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Badhe, A. S. (2017). Flame Stabilization and Lean Blowout Prediction by LES Combustion Model with Strain and Heat Loss Effects. (Thesis). University of Illinois – Chicago. Retrieved from http://hdl.handle.net/10027/22216
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Badhe, Abhijeet Sanjay. “Flame Stabilization and Lean Blowout Prediction by LES Combustion Model with Strain and Heat Loss Effects.” 2017. Thesis, University of Illinois – Chicago. Accessed January 25, 2021.
http://hdl.handle.net/10027/22216.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Badhe, Abhijeet Sanjay. “Flame Stabilization and Lean Blowout Prediction by LES Combustion Model with Strain and Heat Loss Effects.” 2017. Web. 25 Jan 2021.
Vancouver:
Badhe AS. Flame Stabilization and Lean Blowout Prediction by LES Combustion Model with Strain and Heat Loss Effects. [Internet] [Thesis]. University of Illinois – Chicago; 2017. [cited 2021 Jan 25].
Available from: http://hdl.handle.net/10027/22216.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Badhe AS. Flame Stabilization and Lean Blowout Prediction by LES Combustion Model with Strain and Heat Loss Effects. [Thesis]. University of Illinois – Chicago; 2017. Available from: http://hdl.handle.net/10027/22216
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Delft University of Technology
6.
van Haren, Eduard (author).
Effect of H2 Fuel-Addition and Air-Side CO2 Dilution on the Stabilization of Turbulent Dutch Natural Gas Jet Diffusion Flames.
Degree: 2019, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:46a73db1-7ae3-408c-a9d5-d00f58428d71
► The turbulent lifted Dutch natural gas jet diffusion flame in cold co-flowing air is widely used in gas turbine operation and subject of the current…
(more)
▼ The turbulent lifted Dutch natural gas jet diffusion flame in cold co-flowing air is widely used in gas turbine operation and subject of the current investigation. In striving to clean and sustainable combustion, adding hydrogen to the Dutch natural gas (DNG) fuel and CO2 in the coflow is promising. Objective of this investigation is to study the effect of hydrogen fuel-addition and CO2 coflow-dilution on the stability of a turbulent lifted DNG jet diffusion flame in cold co-flowing air. OH* chemiluminescence and particle image velocimetry (PIV) are applied simultaneously at a low sampling frequency of 50 Hz to determine time-averaged statistics of the lift-off height and stabilization point location of the flame. PIV measurements at a sampling frequency of 2.5 kHz are performed to determine the transient behaviour of the stabilization point, the flow conditions at the stabilization point and the burning velocity. Hydrogen fuel-addition leads to increased flame stability. With more hydrogen in the fuel, the lift-off height reduces and the stabilization point location shifts upstream and radially inward. The burning velocity at the stabilization point increases with increasing hydrogen fuel-concentration. A significant difference is observed in the burning velocity conditioned on upstream or downstream stabilization point motion. Hydrogen enables the flame to stabilize in a region of the flow that is characterized by high gas velocity and high vorticity. CO2 dilution of the coflow leads to decreased flame stability. With increasing CO2 coflow-dilution, the lift-off height increases and the stabilization point position shifts downstream and radially outward. The burning velocity at the stabilization point increases with increasing CO2 coflow-dilution and the flame stabilizes in a flow region with significant lower vorticity. Additionally, this report provides useful statistics of the investigated quantities and presents a description for the transient behaviour of the stabilization point.
Mechanical Engineering | Fluid Mechanics
Advisors/Committee Members: Tummers, Mark (mentor), Roekaerts, Dirk (graduation committee), Klein, Sikke (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: Gas Turbines; Lifted Diffusion Jet Flame; Flame Stabilization; Particle Image Velocimetry (PIV); OH Chemiluminescence; Combustion; Hydrogen; Exhaust Gas Recirculation
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
van Haren, E. (. (2019). Effect of H2 Fuel-Addition and Air-Side CO2 Dilution on the Stabilization of Turbulent Dutch Natural Gas Jet Diffusion Flames. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:46a73db1-7ae3-408c-a9d5-d00f58428d71
Chicago Manual of Style (16th Edition):
van Haren, Eduard (author). “Effect of H2 Fuel-Addition and Air-Side CO2 Dilution on the Stabilization of Turbulent Dutch Natural Gas Jet Diffusion Flames.” 2019. Masters Thesis, Delft University of Technology. Accessed January 25, 2021.
http://resolver.tudelft.nl/uuid:46a73db1-7ae3-408c-a9d5-d00f58428d71.
MLA Handbook (7th Edition):
van Haren, Eduard (author). “Effect of H2 Fuel-Addition and Air-Side CO2 Dilution on the Stabilization of Turbulent Dutch Natural Gas Jet Diffusion Flames.” 2019. Web. 25 Jan 2021.
Vancouver:
van Haren E(. Effect of H2 Fuel-Addition and Air-Side CO2 Dilution on the Stabilization of Turbulent Dutch Natural Gas Jet Diffusion Flames. [Internet] [Masters thesis]. Delft University of Technology; 2019. [cited 2021 Jan 25].
Available from: http://resolver.tudelft.nl/uuid:46a73db1-7ae3-408c-a9d5-d00f58428d71.
Council of Science Editors:
van Haren E(. Effect of H2 Fuel-Addition and Air-Side CO2 Dilution on the Stabilization of Turbulent Dutch Natural Gas Jet Diffusion Flames. [Masters Thesis]. Delft University of Technology; 2019. Available from: http://resolver.tudelft.nl/uuid:46a73db1-7ae3-408c-a9d5-d00f58428d71

University of Lund
7.
Kundu, Atanu.
Combustion Characteristics of a Swirl Dry Low Emission
Burner Concept for Gas Turbine Application : Experiments and
Simulations.
Degree: 2016, University of Lund
URL: https://lup.lub.lu.se/record/e6466e5c-fd3c-4d46-8846-30779afe352a
;
https://portal.research.lu.se/ws/files/19310286/Atanu_K_without_papers.pdf
► In the current global energy scenario, gas turbine can provide delicate balance between the booming worlds energy requirement and a pollutant free sustainable society. Cleaner…
(more)
▼ In the current global energy scenario, gas turbine
can provide delicate balance between the booming worlds energy
requirement and a pollutant free sustainable society. Cleaner
combustion of fuel (particular natural gas), efficient, reliable,
low maintenance and cost effective operation of gas turbine
attracted scientific community to push the limit further (high
efficiency and zero emission gas turbine). Gas turbine combustion
process is complex by nature as it interacts with turbulence,
chemical kinetics and thermodynamics. The combined effect directly
affects the component life and cost. To gain deeper understanding
and develop new eco-friendly combustion technology, continuous
effort has been made from last couple of decades. In the present
doctoral thesis, a downscaled prototype dry low emission technology
burner was extensively investigated experimentally. The thesis also
aims to compare the experimental results with numerical
calculations using commercial simulation tools. The main priority
of the research work was to understand the flame stabilization,
flame anchoring physics, the burner operational limits and emission
performance. The gas turbine burner hardware was assembled with
three distinct fuel and sir supply units. Along the centerline, a
primary combustion zone, the RPL (Rich-Pilot-Lean) was placed. A
Pilot and Main stage was placed radially outward direction from the
centerline. A secondary combustion (the main flame) zone was
produced downstream of the burner throat. The primary and secondary
flames were stabilized by the swirling motion of the flow. Vortex
breakdown and recirculation zones assisted the steady combustion
process.Several conventional measurement techniques were employed
for temperature and emission (Carbon monoxide, Nitrogen oxides and
unburned hydrocarbons) measurement. The experimental work in this
thesis also included sophisticated optical measurement. A visually
accessible liner (combustor region with diverging Quarl section)
allowed optical access of the secondary flame region to analyze and
record the flame characteristics. Line of sight Chemiluminescence
(of hydroxyl radical), two dimensional hydroxyls radical planar
laser induced fluorescence and particle image velocimetry
diagnostic techniques were applied to investigate the secondary
combustion (flame front and flow). All the experiments were
conducted at atmospheric condition without any fuel heating.
Chemical kinetic calculations were performed using CHEMKIN software
for comparing the emission results. Steady and un-steady three
dimensional computational fluid dynamic studies were conducted
using ANSYS FLUENT.The RPL combustion produced a hot gas stream and
provided radicals in to the secondary combustion zone (in the
vicinity of forward recirculation zone). Initially, a dedicated
experiment was conducted to explore the operability of the RPL
combustor (primary zone) by varying the equivalence ratios and
co-flow air properties. Results suggested that a slight rich
operation could produce maximum radicals (Carbon…
Subjects/Keywords: Engineering and Technology; Gas Trubine Combustion; Partially Premixed flame; Flame stabilization; Swirl Flow; Emission; Experiments; Combustor; CFD; PLIF; PIV; Chemiluminescence
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APA ·
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MLA ·
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APA (6th Edition):
Kundu, A. (2016). Combustion Characteristics of a Swirl Dry Low Emission
Burner Concept for Gas Turbine Application : Experiments and
Simulations. (Doctoral Dissertation). University of Lund. Retrieved from https://lup.lub.lu.se/record/e6466e5c-fd3c-4d46-8846-30779afe352a ; https://portal.research.lu.se/ws/files/19310286/Atanu_K_without_papers.pdf
Chicago Manual of Style (16th Edition):
Kundu, Atanu. “Combustion Characteristics of a Swirl Dry Low Emission
Burner Concept for Gas Turbine Application : Experiments and
Simulations.” 2016. Doctoral Dissertation, University of Lund. Accessed January 25, 2021.
https://lup.lub.lu.se/record/e6466e5c-fd3c-4d46-8846-30779afe352a ; https://portal.research.lu.se/ws/files/19310286/Atanu_K_without_papers.pdf.
MLA Handbook (7th Edition):
Kundu, Atanu. “Combustion Characteristics of a Swirl Dry Low Emission
Burner Concept for Gas Turbine Application : Experiments and
Simulations.” 2016. Web. 25 Jan 2021.
Vancouver:
Kundu A. Combustion Characteristics of a Swirl Dry Low Emission
Burner Concept for Gas Turbine Application : Experiments and
Simulations. [Internet] [Doctoral dissertation]. University of Lund; 2016. [cited 2021 Jan 25].
Available from: https://lup.lub.lu.se/record/e6466e5c-fd3c-4d46-8846-30779afe352a ; https://portal.research.lu.se/ws/files/19310286/Atanu_K_without_papers.pdf.
Council of Science Editors:
Kundu A. Combustion Characteristics of a Swirl Dry Low Emission
Burner Concept for Gas Turbine Application : Experiments and
Simulations. [Doctoral Dissertation]. University of Lund; 2016. Available from: https://lup.lub.lu.se/record/e6466e5c-fd3c-4d46-8846-30779afe352a ; https://portal.research.lu.se/ws/files/19310286/Atanu_K_without_papers.pdf

Georgia Tech
8.
Wang, Xingjian.
Swirling fluid mixing and combustion dynamics at supercritical conditions.
Degree: PhD, Mechanical Engineering, 2016, Georgia Tech
URL: http://hdl.handle.net/1853/58565
► A unified theoretical and numerical framework is established to study supercritical mixing and combustion over the entire range of fluid thermodynamic states of concern. Turbulence…
(more)
▼ A unified theoretical and numerical framework is established to study supercritical mixing and combustion over the entire range of fluid thermodynamic states of concern. Turbulence closure is achieved using a large-eddy-simulation (LES) technique. A steady laminar flamelet approach is implemented to model turbulence/chemistry interactions. Three-dimensional flow dynamics of a liquid oxygen (LOX) swirl injector at supercritical pressure is studied for the first time. Various mechanisms governing the flow evolution, including hydrodynamic instabilities, acoustic waves, and their interactions are explored using spectral analysis and proper orthogonal decomposition. Then, the mixing and combustion characteristics of LOX/kerosene bi-swirl injectors are investigated under conventional rocket engine operating conditions. Emphasis is placed on the near-field flow and
flame development downstream of the inner swirler. The
flame is stabilized by two counter-rotating vortices in the wake region of the LOX post which is covered by the kerosene-rich mixture. The influence of important injector design attributes, including the recess length, LOX post thickness, and kerosene annulus width, upon mixing and combustion characteristics is examined. The results provide critical information for future injector designs. In addition, counterflow diffusion flames of general fluids are investigated in a wide range of pressures and flow strain rates. An improved two-point
flame-controlling continuation method is employed to solve the singularity problem at the turning points of the
flame-response curve (the S-curve). General similarities are developed in terms of
flame temperature, species concentrations,
flame thickness, and heat-release rate for all pressures of concern. This can be utilized to improve computational efficiency for turbulent combustion models using tabulated chemistry.
Advisors/Committee Members: Lieuwen, Timothy C. (advisor), Yang, Vigor (advisor), Menon, Suresh (committee member), Sun, Wenting (committee member), Ranjan, Devesh (committee member).
Subjects/Keywords: Supercritical fluid; Swirl Injector; Large eddy simulation; Combustion dynamics; Flame stabilization; Liquid oxygen; Kerosene; Flamelet; Counterflow diffusion flame; S-curve
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Wang, X. (2016). Swirling fluid mixing and combustion dynamics at supercritical conditions. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/58565
Chicago Manual of Style (16th Edition):
Wang, Xingjian. “Swirling fluid mixing and combustion dynamics at supercritical conditions.” 2016. Doctoral Dissertation, Georgia Tech. Accessed January 25, 2021.
http://hdl.handle.net/1853/58565.
MLA Handbook (7th Edition):
Wang, Xingjian. “Swirling fluid mixing and combustion dynamics at supercritical conditions.” 2016. Web. 25 Jan 2021.
Vancouver:
Wang X. Swirling fluid mixing and combustion dynamics at supercritical conditions. [Internet] [Doctoral dissertation]. Georgia Tech; 2016. [cited 2021 Jan 25].
Available from: http://hdl.handle.net/1853/58565.
Council of Science Editors:
Wang X. Swirling fluid mixing and combustion dynamics at supercritical conditions. [Doctoral Dissertation]. Georgia Tech; 2016. Available from: http://hdl.handle.net/1853/58565

Mississippi State University
9.
Wu, Wei.
Optical and laser spectroscopic study of microwave plasma-assisted combustion.
Degree: PhD, Applied Physics, 2016, Mississippi State University
URL: http://sun.library.msstate.edu/ETD-db/theses/available/etd-03232016-172605/
;
► Nonthermal plasma-assisted combustion (PAC) has been demonstrated to be a promising potential method to enhance combustion performance and reduce the pollutant emissions. To better…
(more)
▼ Nonthermal plasma-assisted combustion (PAC) has been demonstrated to be a promising potential method to enhance combustion performance and reduce the pollutant emissions. To better understand the mechanism in PAC, we have conducted a series of studies on the combustion enhancement by plasma using a home-developed PAC platform which employs a nonthermal microwave argon plasma and a suit of optical diagnostic tools including optical imaging, optical emission spectroscopy, and cavity ringdown spectroscopy.
A new PAC system in which a continuous atmospheric argon microwave plasma jet is employed to enhance combustion of methane/air mixtures was reported. Reactive species in PAC were characterized in a state-resolved manner including the simultaneously measurements of OH(A) and OH(X) radicals in the PAC flames.
Roles of the state-resolved OH(A) and OH(X) radicals in microwave PAC of premixed methane/air mixture were explored. It was concluded that if both OH(A) and OH(X) radicals assisted the ignition and
flame stabilization processes, then we may hypothesize that the role of OH(A) was more dominant in the ignition enhancement but the role of OH(X) was more dominant in the
flame stabilization.
The effect of fuel injection configurations was investigated in the comparative study between PAC of the premixed and nonpremixed methane/air mixtures. It was found that emissions from the CH (A-X) and C
2 Swan systems only exist in the nonpremixed PAC which suggest that the reaction pathways are different between premixed and nonpremixed PAC.
The PAC of premixed methane/oxygen/argon mixtures was investigated. A U-shaped dual-layer curve of fuel ignition/
flame stabilization limit showing the effects of the plasma power on the fuel ignition and
flame stabilization was observed and reported.
A parametric study of the microwave PAC of the premixed ethylene/air mixtures was conducted. Behavior of the OH, CH, and C
2 radicals and their dependence on plasma power, argon flow rate, and total ethylene/air mixture flow rate were also studied.
Advisors/Committee Members: Chuji Wang (chair), Hendrik F. Arnoldus (committee member), Matthew J. Berg (committee member), Sundar Rajan Krishnan (committee member), Kalyan K. Srinivasan (committee member).
Subjects/Keywords: optical emission spectroscopy; cavity ringdown spectroscopy; flame stabilization; flammability; Plasma; microwave; combustion; plasma-assisted combustion
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Wu, W. (2016). Optical and laser spectroscopic study of microwave plasma-assisted combustion. (Doctoral Dissertation). Mississippi State University. Retrieved from http://sun.library.msstate.edu/ETD-db/theses/available/etd-03232016-172605/ ;
Chicago Manual of Style (16th Edition):
Wu, Wei. “Optical and laser spectroscopic study of microwave plasma-assisted combustion.” 2016. Doctoral Dissertation, Mississippi State University. Accessed January 25, 2021.
http://sun.library.msstate.edu/ETD-db/theses/available/etd-03232016-172605/ ;.
MLA Handbook (7th Edition):
Wu, Wei. “Optical and laser spectroscopic study of microwave plasma-assisted combustion.” 2016. Web. 25 Jan 2021.
Vancouver:
Wu W. Optical and laser spectroscopic study of microwave plasma-assisted combustion. [Internet] [Doctoral dissertation]. Mississippi State University; 2016. [cited 2021 Jan 25].
Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-03232016-172605/ ;.
Council of Science Editors:
Wu W. Optical and laser spectroscopic study of microwave plasma-assisted combustion. [Doctoral Dissertation]. Mississippi State University; 2016. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-03232016-172605/ ;

Michigan Technological University
10.
Ahmed Abdul Moiz.
LOW TEMPERATURE SPLIT INJECTION SPRAY COMBUSTION: IGNITION, FLAME STABILIZATION AND SOOT FORMATION CHARACTERISTICS IN DIESEL ENGINE CONDITIONS.
Degree: PhD, Department of Mechanical Engineering-Engineering Mechanics, 2016, Michigan Technological University
URL: https://digitalcommons.mtu.edu/etdr/253
► The aim of the PhD work is to investigate the fundamental differences in combustion behavior when split injections are used in low temperature combustion…
(more)
▼ The aim of the PhD work is to investigate the fundamental differences in combustion behavior when split injections are used in low temperature combustion regime. In this thesis, the first injection is also called as pilot injection and second injection is also called as main injection. The broad aspects which are studied encompassing the investigation is to study the ignition delay, lift-off and soot formation of such a double split spray combustion. The mechanisms of ignition, lift-off and soot production are to be studied since the main ignition and lift-off were found to differ from the pilot which effect net soot production. The planned studies in the present work are divided into 1) experimental and 2) numerical approaches. Experimental approach involves high-speed schlieren and luminosity imaging to visualize the spray/
flame progress and qualitative soot formation respectively. This is often coupled in a simultaneous way to the laser-based planar laser induced fluorescence (PLIF) technique to visualize ignition behavior in terms of formaldehyde presence and soot precursor visualization of poly-cyclic aromatic hydrocarbons (PAH). As part of CFD simulations, thorough validations of the fuel liquid length, vapor (mixture) presence, temporal and spatial species (formaldehyde, soot) presence, ignition delay, lift-off length, and heat release rate are performed. The main objective of the proposal work would be to perform experimental research with split injection strategies, simulate them using CFD and then understand the underlying mechanisms of important processes of ignition, lift off mechanisms in subsequent injections and the associated soot production mechanisms.
Advisors/Committee Members: Seong-Young Lee.
Subjects/Keywords: Low temperature combustion; multiple injection; split injection; diesel spray; flame stabilization; ignition; Heat Transfer, Combustion
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Moiz, A. A. (2016). LOW TEMPERATURE SPLIT INJECTION SPRAY COMBUSTION: IGNITION, FLAME STABILIZATION AND SOOT FORMATION CHARACTERISTICS IN DIESEL ENGINE CONDITIONS. (Doctoral Dissertation). Michigan Technological University. Retrieved from https://digitalcommons.mtu.edu/etdr/253
Chicago Manual of Style (16th Edition):
Moiz, Ahmed Abdul. “LOW TEMPERATURE SPLIT INJECTION SPRAY COMBUSTION: IGNITION, FLAME STABILIZATION AND SOOT FORMATION CHARACTERISTICS IN DIESEL ENGINE CONDITIONS.” 2016. Doctoral Dissertation, Michigan Technological University. Accessed January 25, 2021.
https://digitalcommons.mtu.edu/etdr/253.
MLA Handbook (7th Edition):
Moiz, Ahmed Abdul. “LOW TEMPERATURE SPLIT INJECTION SPRAY COMBUSTION: IGNITION, FLAME STABILIZATION AND SOOT FORMATION CHARACTERISTICS IN DIESEL ENGINE CONDITIONS.” 2016. Web. 25 Jan 2021.
Vancouver:
Moiz AA. LOW TEMPERATURE SPLIT INJECTION SPRAY COMBUSTION: IGNITION, FLAME STABILIZATION AND SOOT FORMATION CHARACTERISTICS IN DIESEL ENGINE CONDITIONS. [Internet] [Doctoral dissertation]. Michigan Technological University; 2016. [cited 2021 Jan 25].
Available from: https://digitalcommons.mtu.edu/etdr/253.
Council of Science Editors:
Moiz AA. LOW TEMPERATURE SPLIT INJECTION SPRAY COMBUSTION: IGNITION, FLAME STABILIZATION AND SOOT FORMATION CHARACTERISTICS IN DIESEL ENGINE CONDITIONS. [Doctoral Dissertation]. Michigan Technological University; 2016. Available from: https://digitalcommons.mtu.edu/etdr/253
11.
Grib, Stephen William.
LAMINAR AND TURBULENT STUDY OF COMBUSTION IN STRATIFIED ENVIRONMENTS USING LASER BASED MEASUREMENTS.
Degree: 2018, University of Kentucky
URL: https://uknowledge.uky.edu/me_etds/117
► Practical gas turbine engine combustors create extremely non-uniform flowfields, which are highly stratified making it imperative that similar environments are well understood. Laser diagnostics were…
(more)
▼ Practical gas turbine engine combustors create extremely non-uniform flowfields, which are highly stratified making it imperative that similar environments are well understood. Laser diagnostics were utilized in a variety of stratified environments, which led to temperature or chemical composition gradients, to better understand autoignition, extinction, and flame stability behavior. This work ranged from laminar and steady flames to turbulent flame studies in which time resolved measurements were used.
Edge flames, formed in the presence of species stratification, were studied by first developing a simple measurement technique which is capable of estimating an important quantity for edge flames, the advective heat flux, using only velocity measurements. Both hydroxyl planar laser induced fluorescence (OH PLIF) and particle image velocimetry (PIV) were used along with numerical simulations in the development of this technique. Interacting triple flames were also created in a laboratory scale burner producing a laminar and steady flowfield with symmetric equivalence ratio gradients. Studies were conducted in order to characterize and model the propagation speed as a function of the flame base curvature and separation distance between the neighboring flames. OH PLIF, PIV and Rayleigh scattering measurements were used in order to characterize the propagation speed. A model was developed which is capable of accurately representing the propagation speed for three different fuels. Negative edge flames were first studied by developing a one-dimensional model capable of reproducing the energy equation along the stoichiometric line, which was dependent on different boundary conditions. Unsteady and laminar negative edge flames were also simulated with periodic boundary conditions in order to assess the difference between the steady and unsteady cases. The diffusive heat loss was unbalanced with the chemical heat release and advective heat flux energy gain terms which led to the flame proceeding and receding. The temporal derivative balanced the energy equation, but also aided in the understanding of negative edge flame speeds. Turbulent negative edge flame velocities were measured for extinguishing flames in a separate experiment as a function of the bulk advective heat flux through the edge and turbulence level. A burner was designed and built for this study which created statistically stationary negative edge flames. The edge velocity was dependent on both the bulk advective heat flux and turbulence levels. The negative edge flame velocities were obtained with high speed stereo-view chemiluminescence and two dimensional PIV measurements.
Autoignition stabilization was studied in the presence of both temperature and species stratification, using a simple laminar flowfield. OH and CH2O PLIF measurements showed autoignition characteristics ahead of the flame base. Numerical chemical and flow simulations also revealed lower temperature chemistry characteristics ahead of the flame base leading to the conclusion of lower…
Subjects/Keywords: Laser Diagnostics; Edge Flames; Autoignition; Flame Stabilization; Extinction; Heat Transfer, Combustion; Propulsion and Power
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Grib, S. W. (2018). LAMINAR AND TURBULENT STUDY OF COMBUSTION IN STRATIFIED ENVIRONMENTS USING LASER BASED MEASUREMENTS. (Doctoral Dissertation). University of Kentucky. Retrieved from https://uknowledge.uky.edu/me_etds/117
Chicago Manual of Style (16th Edition):
Grib, Stephen William. “LAMINAR AND TURBULENT STUDY OF COMBUSTION IN STRATIFIED ENVIRONMENTS USING LASER BASED MEASUREMENTS.” 2018. Doctoral Dissertation, University of Kentucky. Accessed January 25, 2021.
https://uknowledge.uky.edu/me_etds/117.
MLA Handbook (7th Edition):
Grib, Stephen William. “LAMINAR AND TURBULENT STUDY OF COMBUSTION IN STRATIFIED ENVIRONMENTS USING LASER BASED MEASUREMENTS.” 2018. Web. 25 Jan 2021.
Vancouver:
Grib SW. LAMINAR AND TURBULENT STUDY OF COMBUSTION IN STRATIFIED ENVIRONMENTS USING LASER BASED MEASUREMENTS. [Internet] [Doctoral dissertation]. University of Kentucky; 2018. [cited 2021 Jan 25].
Available from: https://uknowledge.uky.edu/me_etds/117.
Council of Science Editors:
Grib SW. LAMINAR AND TURBULENT STUDY OF COMBUSTION IN STRATIFIED ENVIRONMENTS USING LASER BASED MEASUREMENTS. [Doctoral Dissertation]. University of Kentucky; 2018. Available from: https://uknowledge.uky.edu/me_etds/117

University of Michigan
12.
Upatnieks, Ansis.
Cinema particle image velocimetry investigation of turbulent jet flame stabilization.
Degree: PhD, Pure Sciences, 2002, University of Michigan
URL: http://hdl.handle.net/2027.42/123080
► A new cinema PIV system was developed and used to study the physical phenomena of non-premixed turbulent jet flame stabilization. The system offers an unprecedented…
(more)
▼ A new cinema PIV system was developed and used to study the physical phenomena of non-premixed turbulent jet
flame stabilization. The system offers an unprecedented combination of image acquisition rate (8000/s), sequence length (4000) and resolution (equivalent to 1K x 1.5K pixels) that provides finely resolved yet extraordinarily lengthy time histories of the evolution of velocity fields in laboratory-scale gas-phase turbulent flows. These measurements provide quantitative information concerning the dynamics of turbulence and combustion that is not available from conventional experimental techniques or computational simulations. For example, time histories of the interaction between turbulent vortex structures and the
flame thermal boundary are observed. Gas and
flame velocities are obtained simultaneously, yielding direct measurements of
flame propagation velocities. The gas and
flame velocities are highly correlated, suggesting strong interaction between the velocity field and the
flame. The gas and propagation velocities at the
flame base remain close to premixed laminar burning velocities (S
L), which are three to four times smaller than the velocities in corresponding non-reacting cases. Strong reverse flow is observed upstream of the
flame base, suggesting that the velocity reduction is caused by heat release-induced dilatation. These observations suggest that the dilatation velocity field plays a dominant role in
stabilization by reducing incident gas velocities to levels at which laminar premixed, triple, or edge flames can be sustained.
Advisors/Committee Members: Ceccio, Steven L. (advisor), Driscoll, James F. (advisor).
Subjects/Keywords: Cinema Particle Image Velocimetry; Flame Stabilization; Flow Visualization; Investigation; Jet Flame; Turbulent
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
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APA (6th Edition):
Upatnieks, A. (2002). Cinema particle image velocimetry investigation of turbulent jet flame stabilization. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/123080
Chicago Manual of Style (16th Edition):
Upatnieks, Ansis. “Cinema particle image velocimetry investigation of turbulent jet flame stabilization.” 2002. Doctoral Dissertation, University of Michigan. Accessed January 25, 2021.
http://hdl.handle.net/2027.42/123080.
MLA Handbook (7th Edition):
Upatnieks, Ansis. “Cinema particle image velocimetry investigation of turbulent jet flame stabilization.” 2002. Web. 25 Jan 2021.
Vancouver:
Upatnieks A. Cinema particle image velocimetry investigation of turbulent jet flame stabilization. [Internet] [Doctoral dissertation]. University of Michigan; 2002. [cited 2021 Jan 25].
Available from: http://hdl.handle.net/2027.42/123080.
Council of Science Editors:
Upatnieks A. Cinema particle image velocimetry investigation of turbulent jet flame stabilization. [Doctoral Dissertation]. University of Michigan; 2002. Available from: http://hdl.handle.net/2027.42/123080
13.
Jourdaine, Paul.
Analyse des mécanismes de stabilisation d'oxy-flammes prémélangées swirlées : Stabilization mechanisms analysis of swirled premixed oxy-flames.
Degree: Docteur es, Combustion, 2017, Université Paris-Saclay (ComUE)
URL: http://www.theses.fr/2017SACLC046
► Les travaux présentés dans cette thèse s'inscrivent dans le cadre de la chaire OXYTEC qui regroupe l'entreprise Air Liquide, CentraleSupélec et le CNRS. Ce travail…
(more)
▼ Les travaux présentés dans cette thèse s'inscrivent dans le cadre de la chaire OXYTEC qui regroupe l'entreprise Air Liquide, CentraleSupélec et le CNRS. Ce travail bénéficie également de l'appui de l'ANR. Ce manuscrit fait état des premiers développements et résultats sur le plan expérimental. Un dispositif complet a été développé au laboratoire EM2C pour étudier l'oxy-combustion de flammes stabilisées sur un injecteur tourbillonneur jusqu'à des pressions de 30 bar. Les résultats présentés dans cette thèse ont traits à des prémélanges dont le combustible est du méthane lorsque le foyer opère à pression atmosphérique. Les techniques de LIF-OH, la PIV, la LDV complétées par des mesures de chimiluminescence et de température sont utilisées (1) pour accumuler des données sur la structure de trois flammes de référence CH4/air, CH4/O2/N2 et CH4/O2/CO2 qui sont utilisées pour valider des outils de simulation de la combustion et des transferts thermiques, (2) élucider les mécanismes de stabilisation des oxy-flammes swirlés pré-mélangées à partir d'études paramétriques sur le nombre de swirl, la vitesse débitante, la vitesse laminaire de flamme et l'angle de l'ouvreau de l'injecteur, et (3) comparer la structure des oxy-flammes diluées au CO2 avec des flammes CH4/air en examinant notamment la position de pied de flamme, la topologie générale de la flamme et les températures des parois du foyer.
The work presented in this thesis falls within the framework of the OXYTEC chair, a partnership between Air Liquide, CentraleSupélec and the CNRS. This work also benefits from the support of the ANR. This manuscript reports the first developments and results on the experimental level. A test rig has been developed to study oxy-combustion of swirl-stabilized flames up to pressures of 30 bar. The results presented deal with premixed conditions where the fuel is methaneand the setup is operated at atmospheric pressure. Laser induced fluorescence on the hydroxyl radical, particle imaging velocimetry, Doppler laser velocimetry completed by chemiluminescence imaging and temperature measurements are used to (1) gather data on the structure of three reference flames CH4/air, CH4/O2/N2 and CH4/O2/CO2 which are used to validate simulations of the reacting flow and heat transfer and (2) elucidate the stabilization mechanisms of premixed swirling oxy-flames from parametric studies by varying the swirl number, the bulk injection velocity, the laminar burning velocity and the injector cup angle and (3) compare the structure of CO2 diluted oxy-flames with CH4/air flames by examining the position of the flame leading edge, the general topology of the flame and the temperatures of flow and the combustor walls.
Advisors/Committee Members: Schuller, Thierry (thesis director).
Subjects/Keywords: Oxy-combustion; Swirl; Dilution au CO2; Stabilisation de flamme; Pré-mélange; Oxy-combustion; Swirl; CO2-dilution; Flame stabilization; Premixe
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Jourdaine, P. (2017). Analyse des mécanismes de stabilisation d'oxy-flammes prémélangées swirlées : Stabilization mechanisms analysis of swirled premixed oxy-flames. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2017SACLC046
Chicago Manual of Style (16th Edition):
Jourdaine, Paul. “Analyse des mécanismes de stabilisation d'oxy-flammes prémélangées swirlées : Stabilization mechanisms analysis of swirled premixed oxy-flames.” 2017. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed January 25, 2021.
http://www.theses.fr/2017SACLC046.
MLA Handbook (7th Edition):
Jourdaine, Paul. “Analyse des mécanismes de stabilisation d'oxy-flammes prémélangées swirlées : Stabilization mechanisms analysis of swirled premixed oxy-flames.” 2017. Web. 25 Jan 2021.
Vancouver:
Jourdaine P. Analyse des mécanismes de stabilisation d'oxy-flammes prémélangées swirlées : Stabilization mechanisms analysis of swirled premixed oxy-flames. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2017. [cited 2021 Jan 25].
Available from: http://www.theses.fr/2017SACLC046.
Council of Science Editors:
Jourdaine P. Analyse des mécanismes de stabilisation d'oxy-flammes prémélangées swirlées : Stabilization mechanisms analysis of swirled premixed oxy-flames. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2017. Available from: http://www.theses.fr/2017SACLC046

University of Kentucky
14.
Owens, Tyler.
Flame Stabilization of a Premixed Jet in Vitiated Coflow.
Degree: 2020, University of Kentucky
URL: https://uknowledge.uky.edu/me_etds/159
► Premixed staged combustion in gas turbine engines can reduce emissions by lowering peak flame temperatures but can also lead to different stability characteristics when compared…
(more)
▼ Premixed staged combustion in gas turbine engines can reduce emissions by lowering peak flame temperatures but can also lead to different stability characteristics when compared to traditional combustors. High pressure ratio and subsequently high temperatures can lead to conditions suitable for both autoignition and premixed flame propagation in an environment where spatial fuel/air variations are present.
An experimental facility which issues a premixed jet into a coflowing vitiated mixture was studied to examine the stability behavior, resulting in a lifted flame. The effective ignition delay observed flame was much greater than homogeneous ignition delay calculations for the same conditions. It follows that the heterogeneous environment arising from the mixing between fuel/air jet and vitiated coflow significantly impacts the autoignition behavior.
A numerical simulation modeled with dimensions identical to that of the experimental facility calculated liftoff heights consistent with the experimental flame. Analysis of energy and species balances along streamlines passing through the stabilization region of the flame suggest both premixed and autoignition behavior play a role in its stabilization. Additionally, species concentrations that are typically used for markers for autoignition, such as CH2O, occur due to mixing with autoignition regions rather than being produced on the streamline itself.
Subjects/Keywords: Autoignition; Premixed Combustion; Vitiated Flows; Laminar Flames; Flame Stabilization; Aerodynamics and Fluid Mechanics; Aerospace Engineering; Propulsion and Power
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APA (6th Edition):
Owens, T. (2020). Flame Stabilization of a Premixed Jet in Vitiated Coflow. (Masters Thesis). University of Kentucky. Retrieved from https://uknowledge.uky.edu/me_etds/159
Chicago Manual of Style (16th Edition):
Owens, Tyler. “Flame Stabilization of a Premixed Jet in Vitiated Coflow.” 2020. Masters Thesis, University of Kentucky. Accessed January 25, 2021.
https://uknowledge.uky.edu/me_etds/159.
MLA Handbook (7th Edition):
Owens, Tyler. “Flame Stabilization of a Premixed Jet in Vitiated Coflow.” 2020. Web. 25 Jan 2021.
Vancouver:
Owens T. Flame Stabilization of a Premixed Jet in Vitiated Coflow. [Internet] [Masters thesis]. University of Kentucky; 2020. [cited 2021 Jan 25].
Available from: https://uknowledge.uky.edu/me_etds/159.
Council of Science Editors:
Owens T. Flame Stabilization of a Premixed Jet in Vitiated Coflow. [Masters Thesis]. University of Kentucky; 2020. Available from: https://uknowledge.uky.edu/me_etds/159
15.
Foley, Christopher William.
Attachment point characteristics and modeling of shear layer stabilized flames in an annular, swirling flowfield.
Degree: PhD, Mechanical Engineering, 2015, Georgia Tech
URL: http://hdl.handle.net/1853/54357
► The focus of this work was to develop a deeper understanding of the mechanisms of flame stabilization and extinction for shear layer stabilized, premixed flames.…
(more)
▼ The focus of this work was to develop a deeper understanding of the mechanisms of
flame stabilization and extinction for shear layer stabilized, premixed flames. Planar experimental studies were performed in the attachment point region of an inner shear layer stabilized
flame in an annular, swirl combustor. Through high resolution, simultaneous PIV & CH-PLIF measurements, the instantaneous flow field and
flame position was captured enabling the characterization of 2D
flame stretch and velocity conditions in the attachment point region. In addition, measurements performed at various equivalence ratios and premixer velocities provided insight into the physics governing blowoff. Most notably, these studies showed that as lean blowoff conditions are approached by decreasing equivalence ratio, the mean stretch rates near the attachment point decrease but remain positive throughout the measurement domain. In fact, compared to numerically calculated extinction stretch rates, the
flame becomes less critically stretched as equivalence ratio is decreased. Also, investigation of the
flame structure at the leading edge of the
flame showed strong evidence that the
flame is edge
flame stabilized. This was supported by inspection of the CH-PLIF images, which showed the CH-layer oriented tangent to the flow field and terminating abruptly at the leading edge. Lastly, the
flame anchoring location was observed to be highly robust as the mean
flame edge flow conditions and mean location of leading edge of the
flame were insensitive to changes in equivalence ratio, remaining nearly constant for values ranging from 0.9 to 1.1. However, at the leanest equivalence ratio of 0.8, the
flame leading edge was located farther downstream and
subject to much higher flow velocities. These results thus suggest that blowoff is the result of a kinematic balance and not directly from stretch induced
flame extinction.
Advisors/Committee Members: Lieuwen, Tim (advisor), Seitzman, Jerry (committee member), Zinn, Ben T. (committee member), Renfro, Michael (committee member), Fedorov, Andrei G. (committee member).
Subjects/Keywords: Premixed; Flame stabilization; Stretch; Extinction; Blowoff
…stabilized flames . . . . . . . . . . . . . . . . . . . . . .
23
PREMIXED FLAME STABILIZATION… …168
8.1
Reduced–Order Modeling of Flame Stabilization . . . . . . . . . . . 168
8.2… …and edge flame stabilization . . . .
47
3.1
Test facility schematic… …flame stabilization physics [23] . . . . . . . . . . . . . .
82
4.5
Flow and… …98
4.18 OSL flame stabilization lcomb sensitivity . . . . . . . . . . . . . . . . .
99…
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Foley, C. W. (2015). Attachment point characteristics and modeling of shear layer stabilized flames in an annular, swirling flowfield. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/54357
Chicago Manual of Style (16th Edition):
Foley, Christopher William. “Attachment point characteristics and modeling of shear layer stabilized flames in an annular, swirling flowfield.” 2015. Doctoral Dissertation, Georgia Tech. Accessed January 25, 2021.
http://hdl.handle.net/1853/54357.
MLA Handbook (7th Edition):
Foley, Christopher William. “Attachment point characteristics and modeling of shear layer stabilized flames in an annular, swirling flowfield.” 2015. Web. 25 Jan 2021.
Vancouver:
Foley CW. Attachment point characteristics and modeling of shear layer stabilized flames in an annular, swirling flowfield. [Internet] [Doctoral dissertation]. Georgia Tech; 2015. [cited 2021 Jan 25].
Available from: http://hdl.handle.net/1853/54357.
Council of Science Editors:
Foley CW. Attachment point characteristics and modeling of shear layer stabilized flames in an annular, swirling flowfield. [Doctoral Dissertation]. Georgia Tech; 2015. Available from: http://hdl.handle.net/1853/54357
16.
Pinchak, Matthew D.
Enhanced Flame Stability and Control: The Reacting Jet in
Vitiated Cross-Flow and Ozone-Assisted Combustion.
Degree: PhD, Engineering and Applied Science: Aerospace
Engineering, 2018, University of Cincinnati
URL: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1522319737952261
► The operation of gas turbine engines in increasingly harsh environments while constrained by stringent emissions regulations requires multiple advances in combustion technology. This dissertation addresses…
(more)
▼ The operation of gas turbine engines in increasingly
harsh environments while constrained by stringent emissions
regulations requires multiple advances in combustion technology.
This dissertation addresses two different ways to enhance the
stability and control of the combustion process under such
conditions: the reacting jet in vitiated cross-flow (Part I) and
ozone-assisted combustion (Part II).The first chapter of original
research (Chapter 4) examines several fundamental aspects of the
reacting jet in cross-flow (RJICF). A circular nozzle and high
aspect ratio slotted nozzle of identical area were investigated for
jet to cross-flow momentum flux ratios ranging from
<i>J</i> = 5 to 65 for jet equivalence ratios of up to
φ
j = 5.0. Particle image velocimetry was
utilized to study the flow-field and OH* chemiluminescence was used
to capture features of the
flame behavior. The nozzle geometry was
determined to have a significant effect on RJICF
flame stability,
with substantially expanded blow-out limits for the high aspect
ratio slotted nozzle. Enhanced operability of the slotted nozzle is
attributed to the substantially larger and stronger recirculation
zone on the leeward side of the jet when comparedto the circular
nozzle. This area is characterized by a more disperse region of
elevated vorticity levels, resulting in the entrainment of more hot
combustion products with a longer residence time in the
recirculation zone, which in turn provides a stronger and more
stable ignition source to the oncoming, unburned reactants. The
RJICF is a highly dynamic phenomenon, and its unsteady
characteristics are discussed in Chapter 5. It is shown that both
the non-reacting and reacting flow-fields are characterized by a
peak oscillation frequency present in both the streamwise and
transverse velocity components. The wake Strouhal numbers
(St
w) of the isothermal slotted jet match
values of St
w ≈ 0.13 reported in previous
studies, whereas under combusting conditions
St
w increases from 0.152 to 0.173 as
<i>J</i> is increased from 10 to 35. Proper-orthogonal
decomposition (POD) was performed on the data to extract the
primary coherent structures present in the flow-field. It was shown
that the strongest modes correspond to structures associated with
the fluctuating wake vortices. Chapter 6 investigates the effects
of cross-flow fueling on the RJICF. It is demonstrated that as the
cross-flow equivalence ratio, φ
∞, is
increased, less fuel is required in the jet fluid to stabilize a
flame. For φ
∞ = 0.7, no fuel is required in
the jet and a
flame can be stabilized by a pure air jet. Part II is
an investigation comprised of detailed experiments and numerical
simulations on the effects of the addition of ozone on the
combustion process for gaseous ethylene
(C
2H
4) and liquid
n-heptane (C
7H
16) and
toluene (C
7H
8)
mixtures. The experimental results show increases in the laminar
flame speed when 7.8% of the…
Advisors/Committee Members: Gutmark, Ephraim (Committee Chair).
Subjects/Keywords: Aerospace Materials; Reacting jet in cross flow; Plasma-assisted combustion; Ozone-Assisted Combustion; Particle image velocimetry; Fluidic flame stabilization
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Pinchak, M. D. (2018). Enhanced Flame Stability and Control: The Reacting Jet in
Vitiated Cross-Flow and Ozone-Assisted Combustion. (Doctoral Dissertation). University of Cincinnati. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=ucin1522319737952261
Chicago Manual of Style (16th Edition):
Pinchak, Matthew D. “Enhanced Flame Stability and Control: The Reacting Jet in
Vitiated Cross-Flow and Ozone-Assisted Combustion.” 2018. Doctoral Dissertation, University of Cincinnati. Accessed January 25, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=ucin1522319737952261.
MLA Handbook (7th Edition):
Pinchak, Matthew D. “Enhanced Flame Stability and Control: The Reacting Jet in
Vitiated Cross-Flow and Ozone-Assisted Combustion.” 2018. Web. 25 Jan 2021.
Vancouver:
Pinchak MD. Enhanced Flame Stability and Control: The Reacting Jet in
Vitiated Cross-Flow and Ozone-Assisted Combustion. [Internet] [Doctoral dissertation]. University of Cincinnati; 2018. [cited 2021 Jan 25].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1522319737952261.
Council of Science Editors:
Pinchak MD. Enhanced Flame Stability and Control: The Reacting Jet in
Vitiated Cross-Flow and Ozone-Assisted Combustion. [Doctoral Dissertation]. University of Cincinnati; 2018. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1522319737952261
17.
Lamige, Sylvain.
Analyse de l'influence des conditions aux limites thermiques sur la stabilisation des flammes non-prémélangées : Analysis of the influence of thermal boundary conditions on nonpremixed flame stabilization.
Degree: Docteur es, Thermique - Énergétique, 2014, INSA Lyon
URL: http://www.theses.fr/2014ISAL0099
► La problématique de la stabilisation des flammes non-prémélangées reste primordiale. Il faut pour la résoudre déterminer l’importance relative des phénomènes aérodynamiques, thermiques et chimiques intervenant…
(more)
▼ La problématique de la stabilisation des flammes non-prémélangées reste primordiale. Il faut pour la résoudre déterminer l’importance relative des phénomènes aérodynamiques, thermiques et chimiques intervenant dans les mécanismes de stabilisation. La démarche expérimentale utilisée pour cela au cours de cette thèse porte une attention particulière sur l’influence des conditions aux limites thermiques, et comporte deux volets à travers lesquels le rôle des transferts thermiques est mis en exergue. D’abord, la zone d’attachement d’une flamme stabilisée derrière la lèvre du brûleur est examinée, en considérant les couplages entre le positionnement du bout de flamme à proximité du brûleur et la température de la lèvre. Différentes régions ont ainsi pu être identifiées selon le comportement du bout de flamme, qui évolue depuis une nature diffusive vers une nature propagative à l’approche des limites aérodynamiques de stabilité. Par ailleurs, une modification des propriétés thermiques du brûleur a permis de mettre en évidence une évolution, avec la température de la lèvre, du rôle relatif des modes de coincement thermique et chimique de la flamme par la paroi du brûleur. Ensuite, l’étude concerne non plus un état stabilisé de la flamme, mais les transitions entre les différents régimes de combustion, et plus particulièrement le décrochage d’une flamme attachée. L’examen des conditions conduisant à la déstabilisation de la flamme est un moyen d’apporter des éléments-clefs de compréhension quant aux couplages et aux équilibres aérothermochimiques prévalant préalablement au décrochage. Une évolution du processus de décrochage a ainsi été mise en avant avec l’augmentation de la température initiale des réactants, en lien avec l’évolution de phénomènes transitoires d’extinction locale de la zone de réaction.
Non-premixed flame stabilization is still an important issue in combustion. Addressing this issue requires to evaluate the relative importance of aerodynamic, thermal and chemical phenomena involved in the stabilization mechanisms. This thesis develops to this end an experimental approach, with a particular focus on the influence of thermal boundary conditions, examining the role of heat transfer in a twofold analysis. At first, the attachment zone of a rim-stabilized jet-flame is investigated, by careful consideration of the coupling existing between the burner lip temperature and the flame attachment location relative to the burner. Several regions have been identified according to the flame leading edge behavior, which evolves from diffusive to propagative closer to the aerodynamic stability limits. Besides, by modifying the burner thermal properties, a change has been shown in the relative roles of thermal and chemical quenching of the flame by the burner wall, depending on the burner lip temperature. Secondly, the attention is directed to transitions between different combustion regimes, namely attached and lifted flames. In particular, beyond the stable state of an attached flame, its lifting process is…
Advisors/Committee Members: Escudié, Dany (thesis director).
Subjects/Keywords: Thermique; Transfert de chaleur; Combustion; Flamme; Stabilisation; Conditions aux limites; Flamme attachée; Flamme suspendue; Hystérésis; Thermics; Heat transfer; Combustion; Flame; Stabilization; Attached flame; Lifted flame; Hysteresis; Boundary conditions identification; 536.230 72
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lamige, S. (2014). Analyse de l'influence des conditions aux limites thermiques sur la stabilisation des flammes non-prémélangées : Analysis of the influence of thermal boundary conditions on nonpremixed flame stabilization. (Doctoral Dissertation). INSA Lyon. Retrieved from http://www.theses.fr/2014ISAL0099
Chicago Manual of Style (16th Edition):
Lamige, Sylvain. “Analyse de l'influence des conditions aux limites thermiques sur la stabilisation des flammes non-prémélangées : Analysis of the influence of thermal boundary conditions on nonpremixed flame stabilization.” 2014. Doctoral Dissertation, INSA Lyon. Accessed January 25, 2021.
http://www.theses.fr/2014ISAL0099.
MLA Handbook (7th Edition):
Lamige, Sylvain. “Analyse de l'influence des conditions aux limites thermiques sur la stabilisation des flammes non-prémélangées : Analysis of the influence of thermal boundary conditions on nonpremixed flame stabilization.” 2014. Web. 25 Jan 2021.
Vancouver:
Lamige S. Analyse de l'influence des conditions aux limites thermiques sur la stabilisation des flammes non-prémélangées : Analysis of the influence of thermal boundary conditions on nonpremixed flame stabilization. [Internet] [Doctoral dissertation]. INSA Lyon; 2014. [cited 2021 Jan 25].
Available from: http://www.theses.fr/2014ISAL0099.
Council of Science Editors:
Lamige S. Analyse de l'influence des conditions aux limites thermiques sur la stabilisation des flammes non-prémélangées : Analysis of the influence of thermal boundary conditions on nonpremixed flame stabilization. [Doctoral Dissertation]. INSA Lyon; 2014. Available from: http://www.theses.fr/2014ISAL0099

Georgia Tech
18.
Choi, Woong-Sik.
Flame stabilization by a plasma driven radical jet in a high speed flow.
Degree: PhD, Mechanical Engineering, 2009, Georgia Tech
URL: http://hdl.handle.net/1853/29780
► In current afterburners combustion is stabilized by the high temperature, recirculating region behind bluff body flame holders, such as V-gutters. Blocking the high speed flow…
(more)
▼ In current afterburners combustion is stabilized by the high temperature, recirculating region behind bluff body
flame holders, such as V-gutters. Blocking the high speed flow with bluff bodies causes a significant pressure drop, and heating the
flame holder by the hot combustion product causes a thermal signature, which is a critical problem in a military jet. To reduce these problems, ignition methods using a high frequency (HF) spark discharge, or a radical jet generator (RJG) were developed. The HF discharge ignited and stabilized a
flame successfully in a premixed methane-air flow. The electrical power consumption was very small compared to the combustion heat release, as long as the operating velocity was relatively low. However, a theoretical study showed that the ratio of the electrical power consumption to the heat generation by the stabilized
flame increases rapidly with increasing flow velocity. For
flame stabilization in a high velocity flow, the developed RJG showed much better performance than direct exposure to a plasma. The present study investigated the characteristics of a radical jet produced in a RJG and injected into a main combustor. The limits of
flame stabilization by this jet was measured experimentally, and compared to those of bluff body
flame holders. The
flame holding performance of the radical jet was also experimentally compared to that of a thermal jet. The effect of radicals on
flame stabilization was examined using CHEMKIN, and the limit of
flame stabilization by the radical jet was estimated for a simple flow configuration using an approximate solution. The results suggest that the reduction of local spontaneous ignition delay time by active species in the radical jet and the longer length of a typical radical jet compared to the dimension of the recirculation zone behind a bluff body increases the maximum velocity at which a
flame can be stabilized.
Advisors/Committee Members: Zinn, Ben (Committee Chair), Jagoda, Jeff (Committee Co-Chair), Glezer, Ari (Committee Member), Jeter, Sheldon (Committee Member), Neumeier, Yedidia (Committee Member).
Subjects/Keywords: Electrical discharge; Flame detector; Ignition distance; Ignition delay; Plasma; Flame holder; Radical jet; Flame stabilization; Afterburners; Combustion; Jets Fluid dynamics
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Choi, W. (2009). Flame stabilization by a plasma driven radical jet in a high speed flow. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/29780
Chicago Manual of Style (16th Edition):
Choi, Woong-Sik. “Flame stabilization by a plasma driven radical jet in a high speed flow.” 2009. Doctoral Dissertation, Georgia Tech. Accessed January 25, 2021.
http://hdl.handle.net/1853/29780.
MLA Handbook (7th Edition):
Choi, Woong-Sik. “Flame stabilization by a plasma driven radical jet in a high speed flow.” 2009. Web. 25 Jan 2021.
Vancouver:
Choi W. Flame stabilization by a plasma driven radical jet in a high speed flow. [Internet] [Doctoral dissertation]. Georgia Tech; 2009. [cited 2021 Jan 25].
Available from: http://hdl.handle.net/1853/29780.
Council of Science Editors:
Choi W. Flame stabilization by a plasma driven radical jet in a high speed flow. [Doctoral Dissertation]. Georgia Tech; 2009. Available from: http://hdl.handle.net/1853/29780
19.
Tagliante-Saracino, Fabien.
Combined study by Direct Numerical Simulation and optical diagnostics of the flame stabilization in a diesel spray : Etude combinée par simulation numérique direct et diagnostics optiques de la stabilisation de la flamme d’un spray Diesel.
Degree: Docteur es, Combustion, 2019, Université Paris-Saclay (ComUE)
URL: http://www.theses.fr/2019SACLC017
► La compréhension du processus de stabilisation des flammes Diesel constitue un défi majeur en raison de son effet sur les émissions de polluants. En effet,…
(more)
▼ La compréhension du processus de stabilisation des flammes Diesel constitue un défi majeur en raison de son effet sur les émissions de polluants. En effet, la relation étroite entre la distance de lift-off (distance entre la flamme et l’injecteur) et la production de suie est maintenant bien établie. Cependant, différents mécanismes de stabilisation ont été proposés mais sont toujours sujets à discussion. L'objectif de cette thèse est de fournir une contribution expérimentale et numérique pour identifier les mécanismes de stabilisation majeurs.La combustion d'un spray n-dodécane issu d'un injecteur mono-trou a été étudiée dans une cellule à volume constant en utilisant une combinaison de diagnostics optiques : mesures hautes cadences et simultanées de schlieren, LIF à 355 nm, chimiluminescence haute température ou de chimiluminescence OH *. Des expériences complémentaires sont effectuées au cours desquelles le mélange est allumé entre l’injecteur et le lift-off par plasma induit par laser. L’évolution du lift-off jusqu’à son retour à une position d’équilibre plus en aval est ensuite étudiée pour différentes conditions opératoires. L'analyse de l'évolution du lift-off sans allumage laser révèle deux types principaux de comportement : des sauts brusques en amont et un déplacement plus progressif en aval. Alors que le premier comportement est attribué à des événements d'auto-inflammation, le second est analysé grâce aux résultats obtenus par allumage laser. Il a été constaté que l'emplacement du formaldéhyde avait un impact important sur la vitesse de retour du lift-off.Une simulation numérique directe (DNS en anglais) bidimensionnelle d'une flamme liftée turbulente se développant spatialement dans les mêmes conditions opératoires que les expériences et reproduisant l'évolution temporelle de la distance de lift-off est proposée. Du fait que les expériences montrent que la flamme se stabilise en aval du spray liquide, la DNS ne couvre qu'une région en aval où l’écoulement est réduit à un jet gazeux. La chimie de l’n-dodécane est modélisée à l'aide d'un schéma cinétique (28 espèces transportées) prenant en compte les chemins réactionnels basse et haute température. Comme observé expérimentalement, la stabilisation de la flamme est intermittente : des auto-inflammations se produisent tout d'abord puis se font convecter en aval jusqu'à ce qu'une nouvelle auto-inflammation se produise. Le mécanisme principal de stabilisation est l'auto-inflammation. Toutefois, on observe également à la périphérie du jet diverses topologies de flammes, telles que des flammes triples, qui aident la flamme à se stabiliser en remplissant des réservoirs de gaz brûlés à haute température localisés à la périphérie, ce qui déclenche des auto-inflammations. Toutes ces observations sont résumées dans un modèle conceptuel décrivant la stabilisation de la flamme.Enfin, un modèle prédisant les fluctuations de la distance du lift-off autour de sa valeur moyenne temporelle est proposé. Ce modèle a été développé sur la base d’observations faites dans…
Advisors/Committee Members: Bruneaux, Gilles (thesis director), Angelberger, Christian (thesis director).
Subjects/Keywords: Moteurs à Combustion Interne; Simulation numérique directe; Diagnostics optiques; Stabilisation de la flamme; Direct numerical simulation; Internal Combustion Engines; Optical diagnostics; Flame stabilization
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Tagliante-Saracino, F. (2019). Combined study by Direct Numerical Simulation and optical diagnostics of the flame stabilization in a diesel spray : Etude combinée par simulation numérique direct et diagnostics optiques de la stabilisation de la flamme d’un spray Diesel. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2019SACLC017
Chicago Manual of Style (16th Edition):
Tagliante-Saracino, Fabien. “Combined study by Direct Numerical Simulation and optical diagnostics of the flame stabilization in a diesel spray : Etude combinée par simulation numérique direct et diagnostics optiques de la stabilisation de la flamme d’un spray Diesel.” 2019. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed January 25, 2021.
http://www.theses.fr/2019SACLC017.
MLA Handbook (7th Edition):
Tagliante-Saracino, Fabien. “Combined study by Direct Numerical Simulation and optical diagnostics of the flame stabilization in a diesel spray : Etude combinée par simulation numérique direct et diagnostics optiques de la stabilisation de la flamme d’un spray Diesel.” 2019. Web. 25 Jan 2021.
Vancouver:
Tagliante-Saracino F. Combined study by Direct Numerical Simulation and optical diagnostics of the flame stabilization in a diesel spray : Etude combinée par simulation numérique direct et diagnostics optiques de la stabilisation de la flamme d’un spray Diesel. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2019. [cited 2021 Jan 25].
Available from: http://www.theses.fr/2019SACLC017.
Council of Science Editors:
Tagliante-Saracino F. Combined study by Direct Numerical Simulation and optical diagnostics of the flame stabilization in a diesel spray : Etude combinée par simulation numérique direct et diagnostics optiques de la stabilisation de la flamme d’un spray Diesel. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2019. Available from: http://www.theses.fr/2019SACLC017

University of Illinois – Urbana-Champaign
20.
Rajasegar, Rajavasanth.
Swirl-stabilized lean-premixed flame combustion dynamics: An experimental investigation of flame stabilization, flame dynamics and combustion instability control strategies.
Degree: PhD, Mechanical Engineering, 2018, University of Illinois – Urbana-Champaign
URL: http://hdl.handle.net/2142/100992
► Though modern low-emission combustion strategies have been successful in abating the emission of pollutants in aircraft engines and power generation gas turbines, combustion instability remains…
(more)
▼ Though modern low-emission combustion strategies have been successful in abating the emission of pollutants in aircraft engines and power generation gas turbines, combustion instability remains one of the foremost technical challenges in the development of next generation lean premixed combustor technology. Combustion instability is the coupling between unsteady heat release and combustor acoustic modes where one amplifies the other in a feedback loop. This is a complex phenomenon which involves unsteady chemical kinetic, fluid mechanic and acoustic processes that can lead to unstable behavior and could be detrimental in ways ranging from faster part fatigue to catastrophic system failure. Understanding and controlling the onset and propagation of combustion instability is therefore critical to the development of clean and efficient combustion systems. Imaging of combustion radicals has been a cornerstone diagnostic for the field of combustion for the past two decades which allows for visualization of
flame structure and behavior. However, resolving both temporal and spatial structures from image-based experimental data can be very challenging. Thus, understanding
flame dynamics remains a demanding task and the difficulties often lie in the chaotic and non-linear behavior of the system of interest. To this end, this work investigates the
flame dynamics of lean premixed swirl stabilized flames in two distinct configurations using a variety of high fidelity optical and laser diagnostic techniques in conjunction with advanced data / algorithm based post-processing tools.
The first part of this work is focused on establishing the effectiveness of microwave plasma discharges in improving combustor
flame dynamics through minimizing heat release and pressure fluctuations. The effect of continuous, volumetric, direct coupled, non-equilibrium, atmospheric microwave plasma discharge on a swirl stabilized, lean premixed methane˗air
flame was investigated using quantitative OH planar laser induced fluorescence (PLIF), spectrally resolved emission and acoustic pressure measurements. Proper Orthogonal Decomposition (POD) was used to post-process OH-PLIF images to extract information on
flame dynamics that are usually lost through classical statistical approaches. Results show that direct plasma coupling accelerates combustion chemistry due to the non-thermal effects of plasma that lead to significantly improved combustor dynamics. Overall, this study demonstrates that microwave direct plasma coupling can drastically enhance dynamic
flame stability of swirl stabilized flames especially at very lean operating conditions.
The second part of this work is focused on the development of a stable and efficient small-scale combustor architecture with comparable power density, performance and emission characteristics to that of existing large-scale burners with reduced susceptibility to extinction and externally imposed acoustic perturbations while maintaining high combustion efficiency and low emission levels under ultra-lean…
Advisors/Committee Members: Lee, Tonghun (advisor), Lee, Tonghun (Committee Chair), Stephani, Kelly (committee member), Chamorro, Leonardo P. (committee member), Kriven, Waltraud M. (committee member).
Subjects/Keywords: lean-premixed combustion; swirl stabilization; combustion instability; flame dynamics; Planar Laser Induced Fluorescence (PLIF); Proper Orthogonal Decomposition (POD); Dynamic Mode Decomposition (DMD); direct plasma coupling; mesoscale array
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MLA ·
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APA (6th Edition):
Rajasegar, R. (2018). Swirl-stabilized lean-premixed flame combustion dynamics: An experimental investigation of flame stabilization, flame dynamics and combustion instability control strategies. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/100992
Chicago Manual of Style (16th Edition):
Rajasegar, Rajavasanth. “Swirl-stabilized lean-premixed flame combustion dynamics: An experimental investigation of flame stabilization, flame dynamics and combustion instability control strategies.” 2018. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed January 25, 2021.
http://hdl.handle.net/2142/100992.
MLA Handbook (7th Edition):
Rajasegar, Rajavasanth. “Swirl-stabilized lean-premixed flame combustion dynamics: An experimental investigation of flame stabilization, flame dynamics and combustion instability control strategies.” 2018. Web. 25 Jan 2021.
Vancouver:
Rajasegar R. Swirl-stabilized lean-premixed flame combustion dynamics: An experimental investigation of flame stabilization, flame dynamics and combustion instability control strategies. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2018. [cited 2021 Jan 25].
Available from: http://hdl.handle.net/2142/100992.
Council of Science Editors:
Rajasegar R. Swirl-stabilized lean-premixed flame combustion dynamics: An experimental investigation of flame stabilization, flame dynamics and combustion instability control strategies. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2018. Available from: http://hdl.handle.net/2142/100992
21.
Min, Jiesheng.
Comportement transitionnel et stabilisation de flammes-jets non-prémélangés de méthane dans un coflow d’air dilué en CO2 : Transition and stabilization behaviors of non-premixed methane jet flames insaide an air coflow diluted by carbon dioxide.
Degree: Docteur es, Physique, 2011, Rouen, INSA
URL: http://www.theses.fr/2011ISAM0005
► Ce travail s'intéresse à la compréhension du comportement des flammes non-prémélangées issues d'un jet de méthane assisté par un coflow d'air dilué avec du CO2,…
(more)
▼ Ce travail s'intéresse à la compréhension du comportement des flammes non-prémélangées issues d'un jet de méthane assisté par un coflow d'air dilué avec du CO2, ou d'autres gaz chimiquement inertes pour discriminer les différents phénomènes impliqués dans la dilution. Les phénomènes transitionnels, décrochage et extinction, quantifiés par des limites de stabilité, sont analysés à l'aide de grandeurs physiques représentatives. Le domaine de stabilité de flamme est limité par des surfaces 3D dans le domaine physique ( Qdiluant/Qair (taux de dilution), Uair (vitesse d'air), UCH4 (vitesse de méthane)), révélant un effet compétitif entre l'aérodynamique et la dilution. Des cartographies génériques de décrochage et d'extinction communes à tous ces diluants sont proposées. Des grandeurs liées à la stabilisation sont toutes soumises à des lois d'évolution auto-simlilaires. Il en ressort que la vitesse de propagation de flamme est l'élément clé du mécanisme de stabilisation lors de la dilution.
This work focuses on the understanding of the behaviours of non-premixed methane flame inside an air coflow diluted by carbon dyoxide (CO2) or by other chemically inert diluents in order to discriminate different phenomena involved in dilution. Transitional phenomena (liftoff and extinction) quantified trough the stability limits, are analyzed trough representative physical quantities. The flame stability domain is limited by 3D-surfaces (liftoff and extinction) in the physical domain (Qdiluant/Qair (dilution level), Uair (air velocity), UCH4 (methane velocity)) revealing a competitive effect between aerodynamics and dilution. Generic diagrams of flame liftoff and extinction are proposed for all the diluents. Physical quantities related to flame stabilization process are all submitted to, regardless of diluent, self-similar laws. This is explained by flame burning velocity which is considered as the key element in the flame stabilization mechanism with air-side dilution.
Advisors/Committee Members: Baillot, Françoise (thesis director).
Subjects/Keywords: Dilution de l’air par CO2, N2, Ar; Stabilisation; Décrochage; Extinction; Flamme accrochée, suspendue, de diffusion, partiellement prémélangée; Air-side dilution by CO2, N2, Ar; Stabilization, liftoff, extinction; Attached flame, lifted, non-premixed, partially premixed; Flame burning velocity; LIF-OH, LDV, LII.
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Min, J. (2011). Comportement transitionnel et stabilisation de flammes-jets non-prémélangés de méthane dans un coflow d’air dilué en CO2 : Transition and stabilization behaviors of non-premixed methane jet flames insaide an air coflow diluted by carbon dioxide. (Doctoral Dissertation). Rouen, INSA. Retrieved from http://www.theses.fr/2011ISAM0005
Chicago Manual of Style (16th Edition):
Min, Jiesheng. “Comportement transitionnel et stabilisation de flammes-jets non-prémélangés de méthane dans un coflow d’air dilué en CO2 : Transition and stabilization behaviors of non-premixed methane jet flames insaide an air coflow diluted by carbon dioxide.” 2011. Doctoral Dissertation, Rouen, INSA. Accessed January 25, 2021.
http://www.theses.fr/2011ISAM0005.
MLA Handbook (7th Edition):
Min, Jiesheng. “Comportement transitionnel et stabilisation de flammes-jets non-prémélangés de méthane dans un coflow d’air dilué en CO2 : Transition and stabilization behaviors of non-premixed methane jet flames insaide an air coflow diluted by carbon dioxide.” 2011. Web. 25 Jan 2021.
Vancouver:
Min J. Comportement transitionnel et stabilisation de flammes-jets non-prémélangés de méthane dans un coflow d’air dilué en CO2 : Transition and stabilization behaviors of non-premixed methane jet flames insaide an air coflow diluted by carbon dioxide. [Internet] [Doctoral dissertation]. Rouen, INSA; 2011. [cited 2021 Jan 25].
Available from: http://www.theses.fr/2011ISAM0005.
Council of Science Editors:
Min J. Comportement transitionnel et stabilisation de flammes-jets non-prémélangés de méthane dans un coflow d’air dilué en CO2 : Transition and stabilization behaviors of non-premixed methane jet flames insaide an air coflow diluted by carbon dioxide. [Doctoral Dissertation]. Rouen, INSA; 2011. Available from: http://www.theses.fr/2011ISAM0005

University of Central Florida
22.
Li, Zhiliang.
Experimental And Cfd Investigations Of Lifted Tribrachial Flames.
Degree: 2010, University of Central Florida
URL: https://stars.library.ucf.edu/etd/4204
► Experimental measurements of the lift-off velocity and lift-off height, and numerical simulations were conducted on the liftoff and stabilization phenomena of laminar jet diffusion flames…
(more)
▼ Experimental measurements of the lift-off velocity and lift-off height, and numerical simulations were conducted on the liftoff and
stabilization phenomena of laminar jet diffusion flames of inert-diluted C3H8 and CH4 fuels. Both non-reacting and reacting jets were investigated, including effects of multi-component diffusivities and heat release (buoyancy and gas expansion). The role of Schmidt number for non-reacting jets was investigated, with no conclusive Schmidt number criterion for liftoff previously known in similarity solutions. The cold-flow simulation for He-diluted CH4 fuel does not predict
flame liftoff; however, adding heat release reaction leads to the prediction of liftoff, which is consistent with experimental observations. Including reaction was also found to improve liftoff height prediction for C3H8 flames, with the
flame base location differing from that in the similarity solution - the intersection of the stoichiometric and iso-velocity contours is not necessary for
flame stabilization (and thus lift-off). Possible mechanisms other than that proposed for similarity solution may better help to explain the
stabilization and liftoff phenomena. The stretch rate at a wide range of isotherms near the base of the lifted tribrachial
flame were also quantitatively plotted and analyzed.
Advisors/Committee Members: Chen, Ruey-Hung.
Subjects/Keywords: flame lift-off; CFD simulation; heat release; stretch rate; flame stabilization; buoyancy; Engineering; Mechanical Engineering
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Li, Z. (2010). Experimental And Cfd Investigations Of Lifted Tribrachial Flames. (Doctoral Dissertation). University of Central Florida. Retrieved from https://stars.library.ucf.edu/etd/4204
Chicago Manual of Style (16th Edition):
Li, Zhiliang. “Experimental And Cfd Investigations Of Lifted Tribrachial Flames.” 2010. Doctoral Dissertation, University of Central Florida. Accessed January 25, 2021.
https://stars.library.ucf.edu/etd/4204.
MLA Handbook (7th Edition):
Li, Zhiliang. “Experimental And Cfd Investigations Of Lifted Tribrachial Flames.” 2010. Web. 25 Jan 2021.
Vancouver:
Li Z. Experimental And Cfd Investigations Of Lifted Tribrachial Flames. [Internet] [Doctoral dissertation]. University of Central Florida; 2010. [cited 2021 Jan 25].
Available from: https://stars.library.ucf.edu/etd/4204.
Council of Science Editors:
Li Z. Experimental And Cfd Investigations Of Lifted Tribrachial Flames. [Doctoral Dissertation]. University of Central Florida; 2010. Available from: https://stars.library.ucf.edu/etd/4204
23.
Micka, Daniel James.
Combustion Stabilization, Structure, and Spreading in a Laboratory Dual-Mode Scramjet Combustor.
Degree: PhD, Aerospace Engineering, 2010, University of Michigan
URL: http://hdl.handle.net/2027.42/76012
► Dual-mode scramjets have the potential to provide efficient, air-breathing propulsion at high flight Mach numbers. Flame stabilization and spreading are a challenge in such engines…
(more)
▼ Dual-mode scramjets have the potential to provide efficient, air-breathing propulsion at high flight Mach numbers.
Flame stabilization and spreading are a challenge in such engines due to the very high flow velocities. Combustion occurs in a complex regime where both
flame properties and auto-ignition reactions are expected to be important.
The focus of the current study is to improve the physical understanding of the combustion mechanism and its practical implication in such combustors. Topics of interest are the combustion
stabilization locations, the detailed structure of the reaction zone, and the physical mechanisms controlling the heat release distribution. A facility was developed for the experimental investigation of a laboratory dual-mode scramjet combustor at conditions equivalent to flight Mach numbers of 4.3 to 5.5. The combustor contained flush wall fuel injection and a cavity flameholder, which are the basic flow elements in many proposed practical designs. The diagnostics used include high speed movies of the chemiluminescence, wall pressure measurements, and planar laser induced fluorescence of CH, and simultaneous OH/formaldehyde.
The study revealed two distinct reaction zone structures that are caused by two
flame anchoring locations. Cavity stabilized combustion occurs at low stagnation temperatures. For these conditions the reaction zone is anchored at the cavity leading edge and the
flame spreading is controlled by premixed
flame propagation. Jet-wake stabilized combustion occurs at high stagnation temperatures. The reaction zone is a lifted jet
flame, which has a premixed base and a downstream diffusion
flame. In all cases, initial auto-ignition reactions occur well upstream of the primary reaction zone, resulting in an auto-ignition assisted
flame base. The results are useful for developing physics based models of the combustion.
Advisors/Committee Members: Driscoll, James F. (committee member), Atreya, Arvind (committee member), Carter, Campbell Duncan (committee member), Gruber, Mark Robert (committee member), Ihme, Matthias (committee member).
Subjects/Keywords: Scramjet; Dual-mode Combustor; Flame Stabilization; Auto-ignition; Reaction Zone Structure; PLIF; Aerospace Engineering; Engineering
…92
Flame base stabilization locations… …are two distinct mechanisms for
combustion stabilization; premixed flame propagation and… …regime flame stabilization and stability
are two primary considerations in designing the… …is a somewhat different problem than
flame stabilization. Such combustors would generally… …1.3.1 Combustion Stabilization . . . . . . . . . .
1.3.2 Reaction Zone Imaging…
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Micka, D. J. (2010). Combustion Stabilization, Structure, and Spreading in a Laboratory Dual-Mode Scramjet Combustor. (Doctoral Dissertation). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/76012
Chicago Manual of Style (16th Edition):
Micka, Daniel James. “Combustion Stabilization, Structure, and Spreading in a Laboratory Dual-Mode Scramjet Combustor.” 2010. Doctoral Dissertation, University of Michigan. Accessed January 25, 2021.
http://hdl.handle.net/2027.42/76012.
MLA Handbook (7th Edition):
Micka, Daniel James. “Combustion Stabilization, Structure, and Spreading in a Laboratory Dual-Mode Scramjet Combustor.” 2010. Web. 25 Jan 2021.
Vancouver:
Micka DJ. Combustion Stabilization, Structure, and Spreading in a Laboratory Dual-Mode Scramjet Combustor. [Internet] [Doctoral dissertation]. University of Michigan; 2010. [cited 2021 Jan 25].
Available from: http://hdl.handle.net/2027.42/76012.
Council of Science Editors:
Micka DJ. Combustion Stabilization, Structure, and Spreading in a Laboratory Dual-Mode Scramjet Combustor. [Doctoral Dissertation]. University of Michigan; 2010. Available from: http://hdl.handle.net/2027.42/76012
24.
Soni, Abhishek.
Experimental Investigation of Flame Aerodynamics for
Confined and Unconfined Flow for a Novel Radial-Radial Novel
Injector using 2D Laser Doppler Velocimetry.
Degree: MS, Engineering and Applied Science: Mechanical
Engineering, 2019, University of Cincinnati
URL: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1552656922178471
► Flame stabilization is of fundamental importance in design, efficient performance and the reliable operation of gas turbine combustors. Flame stabilization is generally caused by causing…
(more)
▼ Flame stabilization is of fundamental importance in
design, efficient performance and the reliable operation of gas
turbine combustors.
Flame stabilization is generally caused by
causing combustion products to recirculate and continually ignite
the fuel mixture. The research focus is here to understand the
physics behind
flame stability using flow analysis in gas turbine
combustors. The goal of this research is to investigate the
flame
aerodynamics and combustion for a confined and unconfined swirling
flow using a novel radial-radial injector at standard atmospheric
temperature and pressure using 2D Laser Doppler Velocimetry (LDV).
LDV allows for non-contact measurement with high frequency response
for both the confined and unconfined case. A novel air blast
injector was used for the study since it improves fuel injection
unlike standard swirlers. Experimental investigation has been to
replicate a LDI combustor scenario but without fuels in order to
understand the aerodynamics arising from the interactions of flow
fields by swirl motion caused in confined and unconfined case. The
experiments are performed by placing the chamber with the counter
rotating-radial-radial injector on a horizontally mounted setup
which was moved in the vertical direction as well to record data
for the three axes (X, Y, Z). The inlet air was preheated to 400 F
and the pressure drop across the swirler set to 4% of atmospheric
pressure. The goal of this research work is to improve the
aerodynamics of flow in a confinement and how the aerodynamics of
flame could be enhanced and used to advantage to perform improved
combustion as well as to discern the effects of the novel
properties of the radial-radial injector. The main advantage of
this novel injector was that the surface area of contact between
the fuel and air can be increased which leads to better fuel
distribution. The swirl vane angle was set at 72° with a flow
number of 1.6 and spray angle of 60°. Due to weak laser intensity
of the blue light even after setup orientation, S-N frequency was
found to be less than 50%, hence 2000 particles were considered as
the baseline for data gathering during LDV. The test setup
consisted of a swirler mounted in the centre of the aluminium
chamber (0,0) in terms of coordinate system. A 2-inch x 2-inch
square cross-section plexiglass chamber has been used for flow
field confinement. The measurements were conducted in the
horizontal plane spanning the width of 52 mm and in the vertical
plane up to 28 mm covering the entire spectrum of enclosure to
completely describe the flow fields. This study helped to evaluate
performance for confined and dome recession effects on the flow
fields of novel injector design as well as the unconfined flow
fields in which liquid dominance is near center of the region. Flow
was confined using plexiglass chamber coupled with flow
visualization. The velocity flow fields developed from the swirler
in the confined and unconfined varied greatly in terms of the
recirculation zone development downstream of swirler and closer to…
Advisors/Committee Members: Jeng, San-Mou (Committee Chair).
Subjects/Keywords: Mechanical Engineering; Swirling Flow; Confined and Unconfined; Flame Stabilization; 2D Laser Doppler Velocimetry
…turbine systems employ swirl injectors that produce CTRZ to
dominate the flame stabilization… …instabilities, decreased
flame stabilization and flashback which has restricted the application of LPP… …investigation
of any potential combustion instability and flow-flame dynamics [2].
11
The… …thermal hot-spots in different parts of the engine. Coupling between the flame and
acoustic… …atmospheric nitrogen in high temperature regions of the flame. In order to cut
down the NOx exhaust…
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Soni, A. (2019). Experimental Investigation of Flame Aerodynamics for
Confined and Unconfined Flow for a Novel Radial-Radial Novel
Injector using 2D Laser Doppler Velocimetry. (Masters Thesis). University of Cincinnati. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=ucin1552656922178471
Chicago Manual of Style (16th Edition):
Soni, Abhishek. “Experimental Investigation of Flame Aerodynamics for
Confined and Unconfined Flow for a Novel Radial-Radial Novel
Injector using 2D Laser Doppler Velocimetry.” 2019. Masters Thesis, University of Cincinnati. Accessed January 25, 2021.
http://rave.ohiolink.edu/etdc/view?acc_num=ucin1552656922178471.
MLA Handbook (7th Edition):
Soni, Abhishek. “Experimental Investigation of Flame Aerodynamics for
Confined and Unconfined Flow for a Novel Radial-Radial Novel
Injector using 2D Laser Doppler Velocimetry.” 2019. Web. 25 Jan 2021.
Vancouver:
Soni A. Experimental Investigation of Flame Aerodynamics for
Confined and Unconfined Flow for a Novel Radial-Radial Novel
Injector using 2D Laser Doppler Velocimetry. [Internet] [Masters thesis]. University of Cincinnati; 2019. [cited 2021 Jan 25].
Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1552656922178471.
Council of Science Editors:
Soni A. Experimental Investigation of Flame Aerodynamics for
Confined and Unconfined Flow for a Novel Radial-Radial Novel
Injector using 2D Laser Doppler Velocimetry. [Masters Thesis]. University of Cincinnati; 2019. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=ucin1552656922178471

University of Lund
25.
Subash, Arman.
Laser-Based Investigations of Combustion Phenomena in Gas
Turbine Related Burners.
Degree: 2018, University of Lund
URL: https://lup.lub.lu.se/record/c84e780a-72d0-4e42-815a-e73d1bfa6b32
;
https://portal.research.lu.se/ws/files/36134621/Arman_Subash_PhD_Thesis_2018_LUCRIS.pdf
► Experiments were performed on various combustion devices to investigate the flames employing different optical measurement techniques under atmospheric pressure conditions. Non-intrusive laser-based techniques provided in-situ…
(more)
▼ Experiments were performed on various combustion
devices to investigate the flames employing different optical
measurement techniques under atmospheric pressure conditions.
Non-intrusive laser-based techniques provided in-situ information
concerning different parameters of the combustion process, with a
high degree of temporal and spatial resolution. In the thesis work,
different parameters of interest in combustion research, such as
visualization of different intermediate combustion species and
measurement of the flow velocity field, were studied by use of
laser-induced fluorescence (LIF) and particle image velocimetry
(PIV). The aim was to better understand the reaction and post-flame
zone, flame stabilization, flame-anchoring position, as well as
turbulent-flow interactions under different operating conditions,
while varying the equivalence ratio, Reynolds number, burner
geometry, and composition of fuel employed. Also, high-speed
chemiluminescence imaging was used to investigate the dynamics of
the flame.A large part of the thesis work involves experimental
studies of the flame produced in a downscaled prototype 4th
generation dry low emission (DLE) burner in connection with the
development of the Siemens SGT-750 gas turbine burner. The burner
consists of three concentrically arranged sections: a) an outer
Main section, b) an intermediate section (Pilot) and c) a central
pilot body termed the RPL (Rich-Pilot-Lean) section. Each of these
sections is designed to be premixed and to enable the equivalence
ratio to be varied for achieving optimal combustion. There is a
Quarl, a diverging conical section located at the burner exit, used
for expanding the flow area and holding the flame. Planar
laser-induced fluorescence (PLIF) of OH and chemiluminescence
imaging were employed for studying the flame at the burner exit.
The primary combustion occurred inside the RPL section, whereas the
main combustion was stabilized downstream of the burner throat. The
main flame was anchored inside the Quarl and was elongated within
the combustor. Both the main and the primary flames were stabilized
by the swirling motion of the flow. Vortex breakdown and
recirculation zones assisted the steady combustion process.
Investigations were carried out to study how these three sections
of the burner interact with one other and affect the main
combustion process for altering the operating conditions in each
section separately, using methane (CH4) as fuel. It was found that
the RPL-Pilot flame was mostly confined within the Quarl and played
an essential role in flame stabilization and in locating the
flame-anchoring position. The flame stabilization region moved
downstream when the RPL equivalence ratio (φ) was changed from lean
to rich conditions, whereas it moved upstream when the global φ and
the Pilot φ was increased. The flame was investigated for the
change in geometry that occurred by removing the Quarl to
understand the effect of the Quarl on the flame stabilization.
Significant changes in the flame characteristics were observed for…
Subjects/Keywords: Atom and Molecular Physics and Optics; Combustion; Gas turbine; Chemiluminescence; laser-based techniques; LIF; PIV; DLE; TARS; CH4; H2; OH; CH20; Equivalence ratio; flame stabilization; LBO; Flashback; RPL; Fysicumarkivet A:2018:Subash
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Subash, A. (2018). Laser-Based Investigations of Combustion Phenomena in Gas
Turbine Related Burners. (Doctoral Dissertation). University of Lund. Retrieved from https://lup.lub.lu.se/record/c84e780a-72d0-4e42-815a-e73d1bfa6b32 ; https://portal.research.lu.se/ws/files/36134621/Arman_Subash_PhD_Thesis_2018_LUCRIS.pdf
Chicago Manual of Style (16th Edition):
Subash, Arman. “Laser-Based Investigations of Combustion Phenomena in Gas
Turbine Related Burners.” 2018. Doctoral Dissertation, University of Lund. Accessed January 25, 2021.
https://lup.lub.lu.se/record/c84e780a-72d0-4e42-815a-e73d1bfa6b32 ; https://portal.research.lu.se/ws/files/36134621/Arman_Subash_PhD_Thesis_2018_LUCRIS.pdf.
MLA Handbook (7th Edition):
Subash, Arman. “Laser-Based Investigations of Combustion Phenomena in Gas
Turbine Related Burners.” 2018. Web. 25 Jan 2021.
Vancouver:
Subash A. Laser-Based Investigations of Combustion Phenomena in Gas
Turbine Related Burners. [Internet] [Doctoral dissertation]. University of Lund; 2018. [cited 2021 Jan 25].
Available from: https://lup.lub.lu.se/record/c84e780a-72d0-4e42-815a-e73d1bfa6b32 ; https://portal.research.lu.se/ws/files/36134621/Arman_Subash_PhD_Thesis_2018_LUCRIS.pdf.
Council of Science Editors:
Subash A. Laser-Based Investigations of Combustion Phenomena in Gas
Turbine Related Burners. [Doctoral Dissertation]. University of Lund; 2018. Available from: https://lup.lub.lu.se/record/c84e780a-72d0-4e42-815a-e73d1bfa6b32 ; https://portal.research.lu.se/ws/files/36134621/Arman_Subash_PhD_Thesis_2018_LUCRIS.pdf
26.
Merlo, Nazim.
Caractérisation expérimentale d’une flamme turbulente non prémélangée swirlée : effet de l’enrichissement en oxygène : Experimental characterization of a non-premixed turbulent swirled flame : effect of oxygen enrichment.
Degree: Docteur es, Mécanique des fluides, énergétique, thermique, combustion, 2014, Université d'Orléans
URL: http://www.theses.fr/2014ORLE2058
► Cette thèse est une contribution à l’étude des flammes de méthane turbulentes non prémélangées en rotation, dites swirlées, avec ou sans enrichissement en oxygène de…
(more)
▼ Cette thèse est une contribution à l’étude des flammes de méthane turbulentes non prémélangées en rotation, dites swirlées, avec ou sans enrichissement en oxygène de l’oxydant. L’étude se focalise sur la stabilité de la flamme, les émissions polluantes et la dynamique du jet en non réactif et réactif. Notre dispositif expérimental se compose d’un brûleur à swirler coaxial avec injection radiale de méthane au voisinage de la sortie du brûleur. Ce dernier est confiné dans une chambre de combustion. La teneur en oxygène dans l’oxydant, le nombre de swirl géométrique et la richesse globale à l’injection sont les principaux paramètres qui peuvent être précisément contrôlés. La stabilité de la flamme est caractérisée par chimiluminescence OH*. Les émissions polluantes sont mesurées par des analyseurs en ligne via un prélèvement dans les gaz brûlés. La dynamique du jet est caractérisée principalement par PIV stéréoscopique dans un plan longitudinal et plusieurs plans transverses. La diffusion du méthane dans le jet swirlé est abordée qualitativement par fluorescence induite par laser de l’acétone dans un plan. À ce jour, peu de travaux portent sur la caractérisation notamment dynamique de ces flammes swirlées avec enrichissement en O2. La mise en rotation du jet est à l’origine d’une zone de recirculation centrale qui favorise la stabilisation de la flamme en régime pauvre et à grand nombre de Reynolds. L’étude des émissions polluantes montre que les régimes de combustion à l’air pour lesquels la flamme est liftée stable sont aussi ceux qui produisent du CO et du CH4 résiduel en des quantités non négligeables. L’enrichissement en oxygène permet alors de convertir les imbrûlés et ce pour de faibles enrichissements tout en améliorant la stabilité de flamme via une diminution de la hauteur d’accrochage et des fluctuations associées comme le confirment de précédentes études. L’augmentation des NOx par la voie thermique a été quantifiée pour des enrichissements en oxygène inférieurs à 30 % vol. L’étude systématique en non réactif et réactif apporte des détails sur la topologie tridimensionnelle du jet swirlé suivant les paramètres de l’étude. L’étude de la décroissance des vitesses et de la décroissance du nombre de swirl dans la direction de l’écoulement permetde mettre en évidence l’effet de la flamme sur le jet swirlé. Un couplage entre l’évolution du taux d’entraînement par la recirculation externe et les émissions polluantes est mis en évidence pour expliquer l’évolution des NOx suivant la richesse globale à l’injection. Nous avons proposé une modélisation des écoulements swirlés qui repose sur les écoulements à vorticité hélicoïdale afin d’identifier les caractéristiques principales des structures hélicoïdales au sein de l’écoulement.
This thesis is a contribution to the study of turbulent non-premixed swirling methane flames with or without oxygen addition in the oxidizer. The study deals with the flame stability, the pollutant emissions and the jet dynamic behaviour in non-reacting and reacting conditions. The burner,…
Advisors/Committee Members: Gökalp, Iskender (thesis director).
Subjects/Keywords: Chimiluminescence; Combustion; Emissions polluantes; Enrichissement en oxygène; Flammes non prémélangées; Fluorescence induite par laser (LIF); NOx; Stabilisation; Stéréo vélocimétrie par images de particules (SPIV); Swirl; Vorticité; Chemiluminescence; Combustion; Pollutant emissions; Oxygen enrichment; Non-premixed flames; Laser-Induced Fluorescence (LIF); NOx; Flame stabilization; Stereo particle image velocimetry (SPIV); Swirl; Vorticity; 621.402 3
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APA (6th Edition):
Merlo, N. (2014). Caractérisation expérimentale d’une flamme turbulente non prémélangée swirlée : effet de l’enrichissement en oxygène : Experimental characterization of a non-premixed turbulent swirled flame : effect of oxygen enrichment. (Doctoral Dissertation). Université d'Orléans. Retrieved from http://www.theses.fr/2014ORLE2058
Chicago Manual of Style (16th Edition):
Merlo, Nazim. “Caractérisation expérimentale d’une flamme turbulente non prémélangée swirlée : effet de l’enrichissement en oxygène : Experimental characterization of a non-premixed turbulent swirled flame : effect of oxygen enrichment.” 2014. Doctoral Dissertation, Université d'Orléans. Accessed January 25, 2021.
http://www.theses.fr/2014ORLE2058.
MLA Handbook (7th Edition):
Merlo, Nazim. “Caractérisation expérimentale d’une flamme turbulente non prémélangée swirlée : effet de l’enrichissement en oxygène : Experimental characterization of a non-premixed turbulent swirled flame : effect of oxygen enrichment.” 2014. Web. 25 Jan 2021.
Vancouver:
Merlo N. Caractérisation expérimentale d’une flamme turbulente non prémélangée swirlée : effet de l’enrichissement en oxygène : Experimental characterization of a non-premixed turbulent swirled flame : effect of oxygen enrichment. [Internet] [Doctoral dissertation]. Université d'Orléans; 2014. [cited 2021 Jan 25].
Available from: http://www.theses.fr/2014ORLE2058.
Council of Science Editors:
Merlo N. Caractérisation expérimentale d’une flamme turbulente non prémélangée swirlée : effet de l’enrichissement en oxygène : Experimental characterization of a non-premixed turbulent swirled flame : effect of oxygen enrichment. [Doctoral Dissertation]. Université d'Orléans; 2014. Available from: http://www.theses.fr/2014ORLE2058
27.
Donde, Pratik Prakash.
LES/PDF approach for turbulent reacting flows.
Degree: PhD, Aerospace Engineering, 2012, University of Texas – Austin
URL: http://hdl.handle.net/2152/19481
► The probability density function (PDF) approach is a powerful technique for large eddy simulation (LES) based modeling of turbulent reacting flows. In this approach, the…
(more)
▼ The probability density function (PDF) approach is a powerful technique for large eddy simulation (LES) based modeling of turbulent reacting flows. In this approach, the joint-PDF of all reacting scalars is estimated by solving a PDF transport equation, thus providing detailed information about small-scale correlations between these quantities. The objective of this work is to further develop the LES/PDF approach for studying
flame stabilization in supersonic combustors, and for soot modeling in turbulent flames.
Supersonic combustors are characterized by strong shock-turbulence interactions which preclude the application of conventional Lagrangian stochastic methods for solving the PDF transport equation. A viable alternative is provided by quadrature based methods which are deterministic and Eulerian. In this work, it is first demonstrated that the numerical errors associated with LES require special care in the development of PDF solution algorithms. The direct quadrature method of moments (DQMOM) is one quadrature-based approach developed for supersonic combustion modeling. This approach is shown to generate inconsistent evolution of the scalar moments. Further, gradient-based source terms that appear in the DQMOM transport equations are severely underpredicted in LES leading to artificial mixing of fuel and oxidizer. To overcome these numerical issues, a new approach called semi-discrete quadrature method of moments (SeQMOM) is formulated. The performance of the new technique is compared with the DQMOM approach in canonical flow configurations as well as a three-dimensional supersonic cavity stabilized
flame configuration. The SeQMOM approach is shown to predict subfilter statistics accurately compared to the DQMOM approach.
For soot modeling in turbulent flows, an
LES/PDF approach is integrated with detailed models for soot formation and growth. The PDF approach directly evolves the joint statistics of the gas-phase scalars and a set of moments of the soot number density function. This LES/PDF approach is then used to simulate a turbulent natural gas
flame. A Lagrangian method formulated in cylindrical coordinates solves the high dimensional PDF transport equation and is coupled to an Eulerian LES solver. The LES/PDF simulations show that soot formation is highly intermittent and is always restricted to the fuel-rich region of the flow. The PDF of soot moments has a wide spread leading to a large subfilter variance. Further, the conditional statistics of soot moments conditioned on mixture fraction and reaction progress variable show strong correlation between the gas phase composition and soot moments.
Advisors/Committee Members: Raman, Venkat (advisor), Clemens, Noel (committee member), Ezekoye, Ofodike (committee member), Goldstein, David (committee member), Moser, Robert (committee member).
Subjects/Keywords: Probability density function approach; Large eddy simulation; Supersonic combustion modeling; Soot modeling; Turbulent reacting flows; Direct quadrature method of moments; Semi-discrete quadrature method of moments; Quadrature based methods; Lagrangian Monte Carlo methods; Supersonic combustors; Flame stabilization; Polycyclic aromatic hydrocarbons; Soot-turbulence-chemistry interactions; Shock-turbulence-chemistry interactions
…The
first involves flame stabilization in supersonic combustors, while the second
problem… …1.1 and
1.2. Flame stabilization in supersonic combustors is characterized by strong
shock… …Chapter 6. LES/PDF studies of turbulent
6.1 Delft flame: Simulation details . . . . . .
6.2… …flame… …An experimental turbulent flame producing soot [13]. . . . . .
Schematic of…
Record Details
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Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Donde, P. P. (2012). LES/PDF approach for turbulent reacting flows. (Doctoral Dissertation). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/19481
Chicago Manual of Style (16th Edition):
Donde, Pratik Prakash. “LES/PDF approach for turbulent reacting flows.” 2012. Doctoral Dissertation, University of Texas – Austin. Accessed January 25, 2021.
http://hdl.handle.net/2152/19481.
MLA Handbook (7th Edition):
Donde, Pratik Prakash. “LES/PDF approach for turbulent reacting flows.” 2012. Web. 25 Jan 2021.
Vancouver:
Donde PP. LES/PDF approach for turbulent reacting flows. [Internet] [Doctoral dissertation]. University of Texas – Austin; 2012. [cited 2021 Jan 25].
Available from: http://hdl.handle.net/2152/19481.
Council of Science Editors:
Donde PP. LES/PDF approach for turbulent reacting flows. [Doctoral Dissertation]. University of Texas – Austin; 2012. Available from: http://hdl.handle.net/2152/19481
.