You searched for subject:(combustion speed ).
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University of Manitoba
1.
Gomez Casanova, Carlos Alberto.
Experimental measurement of laminar flame speed of a novel liquid biofuel 1,3 dimethoxyoctane.
Degree: Mechanical Engineering, 2015, University of Manitoba
URL: http://hdl.handle.net/1993/31022 
► Laminar flame speed of a novel liquid bio-fuel has been determined experimentally using a closed spherical combustion vessel of 29 L equipped with two pairs…
(more)
▼ Laminar flame
speed of a novel liquid bio-fuel has been determined experimentally using a closed spherical
combustion vessel of 29 L equipped with two pairs of fused silica windows for optical access at atmospheric pressure and elevated temperature conditions. Schlieren technique was used to visualize and record the temporal evolution of the outwardly spherical flame front, and an in-house developed Matlab code was employed to process the flame front images and calculate its area by applying several image processing techniques. The test conditions consisted of varying the fuel-air mixture equivalence ratio at atmospheric standard pressure and different initial temperatures.
Validation of the present method was achieved by measuring and comparing the flame
speed of methane/air and n-heptane/air mixture with their published counterparts. Experimental results revealed comparable laminar flame
speed of the novel liquid biofuel (1, 3- dimethoxyoctane) to heavy liquid hydrocarbons such as n-heptane and isooctane, especially at stoichiometric and fuel rich conditions. Additionally, the flammability limits of this novel fuel showed similarities with those of gaseous hydrocarbons fuels (e.g. methane, ethane) but higher than those of liquid hydrocarbons (e.g. diesel, gasoline).
Advisors/Committee Members: Birouk, Madjid (Mechanical Engineering) (supervisor), Levin, David (Biosystems Engineering) Wang, Bing-Chen (Mechanical Engineering) (examiningcommittee).
Subjects/Keywords: Laminar flame speed; Biofuel; Combustion
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APA (6th Edition):
Gomez Casanova, C. A. (2015). Experimental measurement of laminar flame speed of a novel liquid biofuel 1,3 dimethoxyoctane. (Masters Thesis). University of Manitoba. Retrieved from http://hdl.handle.net/1993/31022
Chicago Manual of Style (16th Edition):
Gomez Casanova, Carlos Alberto. “Experimental measurement of laminar flame speed of a novel liquid biofuel 1,3 dimethoxyoctane.” 2015. Masters Thesis, University of Manitoba. Accessed January 22, 2021.
http://hdl.handle.net/1993/31022.
MLA Handbook (7th Edition):
Gomez Casanova, Carlos Alberto. “Experimental measurement of laminar flame speed of a novel liquid biofuel 1,3 dimethoxyoctane.” 2015. Web. 22 Jan 2021.
Vancouver:
Gomez Casanova CA. Experimental measurement of laminar flame speed of a novel liquid biofuel 1,3 dimethoxyoctane. [Internet] [Masters thesis]. University of Manitoba; 2015. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/1993/31022.
Council of Science Editors:
Gomez Casanova CA. Experimental measurement of laminar flame speed of a novel liquid biofuel 1,3 dimethoxyoctane. [Masters Thesis]. University of Manitoba; 2015. Available from: http://hdl.handle.net/1993/31022
Northeastern University
2.
Alswat, Mohammed.
Laminar burning speeds and flame structure analysis of gas to liquid (GTL) fuel at high temperatures and pressures.
Degree: PhD, Department of Mechanical and Industrial Engineering, 2017, Northeastern University
URL: http://hdl.handle.net/2047/D20249255
► Laminar burning speed and flame structure of gas-to-liquid (GTL) fuel has been experimentally measured and analyzed using cylindrical vessel. Since GTL is a mixture of…
(more)
▼ Laminar burning speed and flame structure of gas-to-liquid (GTL) fuel has been experimentally measured and analyzed using cylindrical vessel. Since GTL is a mixture of many hydrocarbons, all of the experiments have been done at high temperatures when most constituents have been evaporated. A novel liquid injection system with heating elements have been used to evaporate the liquid fuel before entering to the combustion vessel. Shadowgraph system and a high speed camera that can take up to 40,000 frame per second pictures are set up with the cylindrical vessel to capture the optical recordings of the combustion event. This allows us to observe the flame structure and to investigate the onset of instability.; Laminar burning speeds of mixture of GTL/air have been measured in the cylindrical vessel. The dynamic combustion pressure measured in the cylindrical vessel is the input for the burning model to calculate burning speed. The thermodynamic model used to calculate the burning speed from the pressure rise includes the radiation losses from burned gas to the wall of the vessel, temperature gradient in preheat zone, energy loss to electrodes and convictive energy loss to the wall. NASA polynomial coefficients has been used in the model to calculate the unburned gas properties while STANJAN code was used for the burned gas properties calculation.; Burning speed of GTL/air mixture have been measured for initial temperature of 490 K and a wide range of pressures and equivalence ratios. Power low correlation for burning speed of GTL/air mixture has been developed that is valid in the range of 0.7 < 𜑠< 1.2, 490 K < T < 620 K , 0.5 atm < P < 4.3 atm. Based on the burning speed results, it was noted that the laminar burning speed is proportional directly to temperature and inversely to pressure.
Subjects/Keywords: laminar burning speed; gas-to-liquid; combustion
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APA (6th Edition):
Alswat, M. (2017). Laminar burning speeds and flame structure analysis of gas to liquid (GTL) fuel at high temperatures and pressures. (Doctoral Dissertation). Northeastern University. Retrieved from http://hdl.handle.net/2047/D20249255
Chicago Manual of Style (16th Edition):
Alswat, Mohammed. “Laminar burning speeds and flame structure analysis of gas to liquid (GTL) fuel at high temperatures and pressures.” 2017. Doctoral Dissertation, Northeastern University. Accessed January 22, 2021.
http://hdl.handle.net/2047/D20249255.
MLA Handbook (7th Edition):
Alswat, Mohammed. “Laminar burning speeds and flame structure analysis of gas to liquid (GTL) fuel at high temperatures and pressures.” 2017. Web. 22 Jan 2021.
Vancouver:
Alswat M. Laminar burning speeds and flame structure analysis of gas to liquid (GTL) fuel at high temperatures and pressures. [Internet] [Doctoral dissertation]. Northeastern University; 2017. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/2047/D20249255.
Council of Science Editors:
Alswat M. Laminar burning speeds and flame structure analysis of gas to liquid (GTL) fuel at high temperatures and pressures. [Doctoral Dissertation]. Northeastern University; 2017. Available from: http://hdl.handle.net/2047/D20249255
University of Illinois – Urbana-Champaign
3.
Mitsingas, Constandinos Miltiadis.
Reactive flow visualization through high-speed optical laser diagnostics.
Degree: PhD, Mechanical Engineering, 2018, University of Illinois – Urbana-Champaign
URL: http://hdl.handle.net/2142/101758
► Turbulent combustion is a complex phenomenon that involves the interaction between fluid mechanics and chemical kinetics. Turbulence plays an important role in combustion because it…
(more)
▼ Turbulent
combustion is a complex phenomenon that involves the interaction between fluid mechanics and chemical kinetics. Turbulence plays an important role in
combustion because it ensures a thorough mixing between the oxidizer and fuel at a molecular level. Improper mixing can lead to incomplete
combustion, resulting in increased emissions and decreased flame stability. Hence, understanding and controlling the coupling between chemical kinetics and turbulence can lead to significant improvements in the design of
combustion systems, improving their stability, efficiency and emissions characteristics.
In this study, a method was demonstrated using temporally-resolved laser diagnostics to visualize: 1) The turbulent flow field with particle image velocimetry (PIV); and 2) the distribution of
combustion radicals, by planar laser-induced fluorescence (PLIF). This allows for the visualization of the flame surface behavior, while at the same time linking it to inherent flow and
combustion instabilities. Characterizing turbulence requires high temporal resolution and combining it with high-
speed combustion radical imaging adds an additional diagnostics challenge. Trying to extend the capabilities of current laser diagnostics techniques to higher repetition rates to achieve the desired temporal resolution in order to resolve turbulence is a major issue due to limitations in terms of laser power scalability with repetition rate. In this work, a new approach is investigated that reduces the overall laser power required to visualize the flame structure (CH and OH radicals) while allowing for simultaneous flow field imaging at high repetition rates (10 kHz).
A comprehensive study of CH-PLIF imaging using the of the CH molecule to visualize the flame reaction zone is presented here. The CH-PLIF imaging effectiveness and its suitability for use in conjunction with PIV were quantified using a laminar Bunsen flame. Due to the high Einstein coefficients, the Q-branch rotational excitation strategy has the lowest laser power requirements and hence is best suited for high-
speed imaging. However, isolating the fluorescence signal from the excitation wavelength is a major concern especially in high-scattering environments, due to the inherent resonant transition that is observed in the Q-branch excitation strategy.
To address this, the excitation scheme was switched to the weaker (by a factor of 5) R-branch transition, whose fluorescence signal proved to be sufficient for CH-imaging, with separation of the fluorescence and excitation wavelengths through the use of a custom-made sharp cut-off edge filter. The low laser pulse energy requirements of this transition combined with the use of the custom edge filter allowed for simultaneous 10 kHz CH-PLIF and PIV imaging in a highly turbulent Hi-Pilot burner (ReT ~ 7900). Reaction layer thicknesses were estimated from the CH-PLIF images, and their interaction with the flow field was observed. Folding of the flame sheet caused an interaction between the out-of-plane and in-plane flame…
Advisors/Committee Members: Lee, Tonghun (advisor), Lee, Tonghun (Committee Chair), Bodony, Daniel (committee member), Bahl, Gaurav (committee member), Chamorro, Leonardo (committee member).
Subjects/Keywords: High-speed; laser diagnostics; CH-PLIF; Combustion
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APA (6th Edition):
Mitsingas, C. M. (2018). Reactive flow visualization through high-speed optical laser diagnostics. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/101758
Chicago Manual of Style (16th Edition):
Mitsingas, Constandinos Miltiadis. “Reactive flow visualization through high-speed optical laser diagnostics.” 2018. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed January 22, 2021.
http://hdl.handle.net/2142/101758.
MLA Handbook (7th Edition):
Mitsingas, Constandinos Miltiadis. “Reactive flow visualization through high-speed optical laser diagnostics.” 2018. Web. 22 Jan 2021.
Vancouver:
Mitsingas CM. Reactive flow visualization through high-speed optical laser diagnostics. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2018. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/2142/101758.
Council of Science Editors:
Mitsingas CM. Reactive flow visualization through high-speed optical laser diagnostics. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2018. Available from: http://hdl.handle.net/2142/101758
4.
Mazur, Marek.
Etude expérimentale du bruit de combustion dans un foyer de type aéronautique : Experimental study of combustion noise in an aeronautic type combustion chamber.
Degree: Docteur es, Combustion, 2017, Université Paris-Saclay (ComUE)
URL: http://www.theses.fr/2017SACLC034
► Le bruit de combustion est devenu un contributeur de plus en plus important dans le bruit total de moteur d'avion. Ce bruit global a deux…
(more)
▼ Le bruit de combustion est devenu un contributeur de plus en plus important dans le bruit total de moteur d'avion. Ce bruit global a deux composantes: Le bruit direct et le bruit indirect. Le premier est issu des fluctuations de dégagement de chaleur dans la flamme elle-même. Le deuxième a pour origine les inhomogénéités de température dans les gaz brûlés. L'objectif de ce travail est la conception d'un banc de combustion sous pression avec une flamme pauvre, prémélangée swirlée dont les paramètres d'injection permettront d'obtenir des grandes quantités de bruit indirect.Il est nécessaire de caractériser ce banc et d'établir quelle est la part du bruit direct et de l'indirect afin d'identifier les sources de ces contributions. Pour cette caractérisation il est nécessaire d'utiliser différents diagnostics, de prendre en compte la résolution temporelle. Ces diagnostics à haute cadence permettent de caractériser les champs de vitesse et les dynamiques de flamme, les instabilités de combustion dans le système et ainsi évaluer les contributions du bruit direct et indirect.
Combustion noise has become an increasing contributor of overall aircraft engine noise. It consists of two major parts, direct and indirect combustion noise. The former is generated by the heat release fluctuations of the flame itself. The latter is generated by the temperature inhomogeneities in the burnt gases, which are accelerated in the turbine stages or nozzle following the combustion chamber.The aim of this work is to design and build a pressurized lean swirling combustor test bench, in order to quantify the two contributions.The combustor is thus supposed to generate high quantities of indirect combustion noise. The second aim is then to determine the contributions of direct and indirect combustion noise quantitatively and to gain insight about the sources of the two contributions. These analyses are conducted by different high-speed diagnostics, which were worked on during this work. These diagnostics allow to characterize the flow fields and flame dynamics, to put forward the combustion instability in the system and finally to quantify the direct and indirect combustion noise contributions.
Advisors/Committee Members: Ducruix, Sébastien (thesis director), Richecœur, Franck (thesis director), Scouflaire, Philippe (thesis director).
Subjects/Keywords: Bruit de combustion; Bruit entropique; Instabilité de combustion; Diagnostics à haute cadence; Combustion noise; Entropy noise; Combustion instability; High-Speed diagnostics
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APA (6th Edition):
Mazur, M. (2017). Etude expérimentale du bruit de combustion dans un foyer de type aéronautique : Experimental study of combustion noise in an aeronautic type combustion chamber. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2017SACLC034
Chicago Manual of Style (16th Edition):
Mazur, Marek. “Etude expérimentale du bruit de combustion dans un foyer de type aéronautique : Experimental study of combustion noise in an aeronautic type combustion chamber.” 2017. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed January 22, 2021.
http://www.theses.fr/2017SACLC034.
MLA Handbook (7th Edition):
Mazur, Marek. “Etude expérimentale du bruit de combustion dans un foyer de type aéronautique : Experimental study of combustion noise in an aeronautic type combustion chamber.” 2017. Web. 22 Jan 2021.
Vancouver:
Mazur M. Etude expérimentale du bruit de combustion dans un foyer de type aéronautique : Experimental study of combustion noise in an aeronautic type combustion chamber. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2017. [cited 2021 Jan 22].
Available from: http://www.theses.fr/2017SACLC034.
Council of Science Editors:
Mazur M. Etude expérimentale du bruit de combustion dans un foyer de type aéronautique : Experimental study of combustion noise in an aeronautic type combustion chamber. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2017. Available from: http://www.theses.fr/2017SACLC034
McMaster University
5.
Strack, James M.
A New Pool Boiling Facility for the Study of Nanofluids.
Degree: MASc, 2013, McMaster University
URL: http://hdl.handle.net/11375/12879
► Nanofluids are engineered colloidal dispersions of nanoparticles in a liquid. The field of nanofluids has seen much interest due to reported heat transfer enhancements…
(more)
▼ Nanofluids are engineered colloidal dispersions of nanoparticles in a liquid. The field of nanofluids has seen much interest due to reported heat transfer enhancements over the corresponding pure fluids at low particle concentrations. Particularly, a large increase in critical heat flux (CHF) has been widely reported along with modification of the boiling interface. Inconsistencies in reported impact on nucleate boiling heat transfer and the degree of CHF enhancement illustrate the need for further study. A pool boiling experiment has been designed and constructed at McMaster University to allow for the study the boiling of water-based nanofluids. The facility has been commissioned with saturated distilled water tests at atmospheric pressure, heat flux levels up to 1200 kW·m-2, and at wall superheat levels up to 19.5oC. Wall superheat and heat flux uncertainties were estimated to be ±0.6oC and ±20 kW∙m-2, respectively. For the installed test section, heat flux is limited to 2.62 ± 0.06 MW·m-2. A high speed video system for the analysis of bubble dynamics was tested and used for qualitative comparisons between experimental runs. This system was tested at 2500 FPS and an imaging resolution of 39 pixels per mm, but is capable of up to 10 000 FPS at the same spatial resolution. Heat flux versus wall superheat data was compared to the Rohsenow correlation and found to qualitatively agree using surface factor <em>Csf</em> = 0.011. Results were found to have a high degree of repeatability at heat flux levels higher than 600 kW·m-2. The new facility will be used to conduct studies into the pool boiling of saturated water-based nanofluids at atmospheric pressure. Additional work will involve the control and characterization of heater surface conditions before and after boiling. Quantitative analysis of bubble dynamics will be possible using high speed video and particle image velocimetry.
Master of Applied Science (MASc)
Advisors/Committee Members: Novog, D. R., Engineering Physics.
Subjects/Keywords: nanofluids; pool boiling; high speed video; experiment design; Heat Transfer, Combustion; Heat Transfer, Combustion
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APA (6th Edition):
Strack, J. M. (2013). A New Pool Boiling Facility for the Study of Nanofluids. (Masters Thesis). McMaster University. Retrieved from http://hdl.handle.net/11375/12879
Chicago Manual of Style (16th Edition):
Strack, James M. “A New Pool Boiling Facility for the Study of Nanofluids.” 2013. Masters Thesis, McMaster University. Accessed January 22, 2021.
http://hdl.handle.net/11375/12879.
MLA Handbook (7th Edition):
Strack, James M. “A New Pool Boiling Facility for the Study of Nanofluids.” 2013. Web. 22 Jan 2021.
Vancouver:
Strack JM. A New Pool Boiling Facility for the Study of Nanofluids. [Internet] [Masters thesis]. McMaster University; 2013. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/11375/12879.
Council of Science Editors:
Strack JM. A New Pool Boiling Facility for the Study of Nanofluids. [Masters Thesis]. McMaster University; 2013. Available from: http://hdl.handle.net/11375/12879
Universidade do Rio Grande do Sul
6.
Andrade, Giovanni Souza de.
Avaliação experimental da duração de combustão para diferentes combustÃveis, em um motor padrão Ciclo Otto ASTM-CFR.
Degree: 2007, Universidade do Rio Grande do Sul
URL: http://hdl.handle.net/10183/10185
► Neste trabalho se desenvolve e se avalia uma metodologia para determinar a duração de combustão de alguns combustÃveis em um motor padrão à combustão interna…
(more)
▼ Neste trabalho se desenvolve e se avalia uma metodologia para determinar a duração de combustão de alguns combustÃveis em um motor padrão à combustão interna (ASTM-CFR - Cooperative Fuel Research), tendo-se em conta que a duração da combustão está relacionada com a velocidade de propagação da chama e que a relação de compressão, a condição de mistura ar-combustÃvel e a turbulência na câmara de combustão, entre outros fatores, influenciam a duração da combustão. Assim, quanto maior a velocidade de propagação da chama, menor deverá ser o trabalho negativo necessário para comprimir a mistura antes do ponto morto superior, aumentando, assim, a eficiência do ciclo. Em cada bateria de testes, utilizou-se um combustÃvel de composição quÃmica conhecida para seis relações de ar-combustÃvel e quatro relações de compressão, sendo eles: o Etanol, o Metanol, o Metil Terc Butil Éter (MTBE) e compostos aromáticos como Tolueno, Etilbenzeno e Xilenos. Determinou-se o tempo de combustão dos combustÃveis, em um motor CFR, em função da variação da relação de compressão e razão de mistura ar-combustÃvel.
This work develops and evaluates a methodology to determine combustion duration for several fuels in a standard internal combustion engine (ASTM-CFR - Cooperative Fuel Research). Combustion duration is related to flame speed, compression ratio, air fuel ratio, turbulence inside the combustion chamber and some other factors. Hence, the bigger the flame speed, the smaller the negative work done by the piston to compress the mixture before top dead center, leading to a smaller heat loss during combustion and to a higher efficiency over the whole cycle. In each test batch it was used a fuel with a known chemical structure, for 6 different air fuel ratios and 4 different compression ratios. The fuels used were Ethanol, Methanol, Methyl Tertiary-Butyl Ether (MTBE) and some aromatics such as Toluene, Ethylbenzene and Xylene. The time of combustion of fuels was determined, in an engine CFR, function of the variation of the relation of compression and mixture ratio air-fuel.
Advisors/Committee Members: Mello, Pedro Barbosa.
Subjects/Keywords: Motor de combustão interna; Fuel; CombustÃveis; Combustion; ASTM-CFR; Speed flame
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APA (6th Edition):
Andrade, G. S. d. (2007). Avaliação experimental da duração de combustão para diferentes combustÃveis, em um motor padrão Ciclo Otto ASTM-CFR. (Thesis). Universidade do Rio Grande do Sul. Retrieved from http://hdl.handle.net/10183/10185
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):
Andrade, Giovanni Souza de. “Avaliação experimental da duração de combustão para diferentes combustÃveis, em um motor padrão Ciclo Otto ASTM-CFR.” 2007. Thesis, Universidade do Rio Grande do Sul. Accessed January 22, 2021.
http://hdl.handle.net/10183/10185.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Andrade, Giovanni Souza de. “Avaliação experimental da duração de combustão para diferentes combustÃveis, em um motor padrão Ciclo Otto ASTM-CFR.” 2007. Web. 22 Jan 2021.
Vancouver:
Andrade GSd. Avaliação experimental da duração de combustão para diferentes combustÃveis, em um motor padrão Ciclo Otto ASTM-CFR. [Internet] [Thesis]. Universidade do Rio Grande do Sul; 2007. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/10183/10185.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Andrade GSd. Avaliação experimental da duração de combustão para diferentes combustÃveis, em um motor padrão Ciclo Otto ASTM-CFR. [Thesis]. Universidade do Rio Grande do Sul; 2007. Available from: http://hdl.handle.net/10183/10185
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Texas A&M University
7.
Shoyinka, Ayobami Oluwapelumi.
Ultra-High-Speed Laser-Induced Breakdown Spectroscopy (LIBS) Applications Using a Pulse-Burst Laser System.
Degree: MS, Mechanical Engineering, 2019, Texas A&M University
URL: http://hdl.handle.net/1969.1/187536
► Laser-induced breakdown spectroscopy (LIBS) is a technique that utilizes intense laser pulses to generate a localized plasma that can be used for chemical analysis via…
(more)
▼ Laser-induced breakdown spectroscopy (LIBS) is a technique that utilizes intense laser pulses to generate a localized plasma that can be used for chemical analysis via quantifying the elemental composition of a sample. During the LIBS process, the emission generated from the plasma is collected, sent through a spectrometer and typically imaged using an intensified charged coupled devices (CCD) array. Unique spectral lines can then be detected, quantified, and assigned to specific elements that make up the sample. For the first time, to the best of our knowledge, a custom-designed pulse-burst laser operating at 100-kHz repetition rate was used for an ultra-high-
speed LIBS application. While conventional LIBS methods utilize 10-Hz repetition-rate lasers, the higher repetition rate of 100-kHz allows for a faster sampling rate; specifically, during high-
speed, short duration events such as explosions and shockwaves. Consequently, the potential benefits and applications of ultra-high-
speed LIBS were explored using the pulse-burst laser system. In the preliminary studies, solid aluminum and copper targets were used for system characterization and calibration. Further studies were conducted to quantify the capabilities of high-
speed LIBS for applications involving dynamic events lasting several milliseconds or less. Under the current experimental conditions, LIBS emissions from a high-exit-velocity air nozzle with additives of aerosol compounds were clearly recognized and detected at a high hit rate. Upon successful applications of the pulse-burst laser for preliminary testing, experiments were conducted during
combustion of hydroxyl-terminated polybutadiene/ammonium perchlorate (HTPB/AP) propellants doped with varying concentrations of metals consisting of aluminum (Al), and lead (Pb). The pulse-burst laser LIBS system was successful in detecting the released metallic particles within the hot reaction zone of HTPB/AP propellants. A calibration study showed a relationship between the concentration of metals within the propellants and the hit rate at which the pulse-burst laser pulses interact with metallic particles. The limit of detection (LOD) of metal particles in the hot reaction zone was successfully calculated for subsequent applications of the pulse-burst-laser-based LIBS for predicting the metallic concentration with respect to the baseline case of 16% aluminum propellant samples.
Advisors/Committee Members: Kulatilaka, Waruna D (advisor), Petersen, Eric L (committee member), Sokolov, Alexei V (committee member).
Subjects/Keywords: Pulse-burst; Spectroscopy; Laser-induced breakdown; High-speed combustion diagnostics
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APA (6th Edition):
Shoyinka, A. O. (2019). Ultra-High-Speed Laser-Induced Breakdown Spectroscopy (LIBS) Applications Using a Pulse-Burst Laser System. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/187536
Chicago Manual of Style (16th Edition):
Shoyinka, Ayobami Oluwapelumi. “Ultra-High-Speed Laser-Induced Breakdown Spectroscopy (LIBS) Applications Using a Pulse-Burst Laser System.” 2019. Masters Thesis, Texas A&M University. Accessed January 22, 2021.
http://hdl.handle.net/1969.1/187536.
MLA Handbook (7th Edition):
Shoyinka, Ayobami Oluwapelumi. “Ultra-High-Speed Laser-Induced Breakdown Spectroscopy (LIBS) Applications Using a Pulse-Burst Laser System.” 2019. Web. 22 Jan 2021.
Vancouver:
Shoyinka AO. Ultra-High-Speed Laser-Induced Breakdown Spectroscopy (LIBS) Applications Using a Pulse-Burst Laser System. [Internet] [Masters thesis]. Texas A&M University; 2019. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/1969.1/187536.
Council of Science Editors:
Shoyinka AO. Ultra-High-Speed Laser-Induced Breakdown Spectroscopy (LIBS) Applications Using a Pulse-Burst Laser System. [Masters Thesis]. Texas A&M University; 2019. Available from: http://hdl.handle.net/1969.1/187536
Northeastern University
8.
Elia, Mimmo.
Measurement apparatus and modelling of laminar burning speed and mass burning rate of syngas and onset of auto-ignition of N-heptane and gas to liquid fuel.
Degree: PhD, Department of Mechanical and Industrial Engineering, 2016, Northeastern University
URL: http://hdl.handle.net/2047/D20211318
► Research studies into understanding the fundamental thermodynamic properties of Syngas are extremely relevant in engineering combustion modelling for stationary turbine based power plants and for…
(more)
▼ Research studies into understanding the fundamental thermodynamic properties of Syngas are extremely relevant in engineering combustion modelling for stationary turbine based power plants and for IC engines. The models rely heavily on accurate experimental results and of critical importance is the data for: chemical kinetic rates, mass burning rate and auto-ignition conditions. To produce some of this necessary data, an experimental facility capable of measuring the pressure rise from spherically expanding flames was developed. The first core component of the facility includes a spherical combustion vessel that enables the measurement of the pressure rise from a combustion process, at high initial temperature and pressure. The second core component of the facility, which includes a lower pressure cylindrical combustion vessel, with optically clear sides, enables the direct measurement of laminar flame speed as well as the visualization of expanding spherical flames for the study of flame structures. An improved model to complement the experimental measurements has been developed. Using the thermodynamic model, the mass burning rate and laminar burning speed can be calculated from the pressure data measured using one of the two constant volume combustion vessels. The model is used to calculate the mass fraction of the burned gas by simultaneously solving the conservation of mass and energy equations coupled with equilibrium concentrations calculation of the combustion products using STANJAN. For smooth non-cellular flames laminar burning speed can be also calculated. The facility and model have been used and improved by many of the researchers at Northeastern University with results published in a variety of technical journals, and thus expanding the measured range of laminar flame speed. This thesis will describe in detail the experimental apparatus and report the laminar burning speed and mass burning rate for Syngas-Air and Syngas-O2-He at high temperature and pressure as well as auto-ignition characteristics of n-Heptane and GTL (S8), which is a synthetic surrogate for aviation fuel.
Subjects/Keywords: auto-ignition; GTL; laminar burning speed; mass burning speed; S8; syngas; Synthesis gas; Combustion; Combustion; Combustion chambers; Gas as fuel; Flame; Chemical kinetics
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APA (6th Edition):
Elia, M. (2016). Measurement apparatus and modelling of laminar burning speed and mass burning rate of syngas and onset of auto-ignition of N-heptane and gas to liquid fuel. (Doctoral Dissertation). Northeastern University. Retrieved from http://hdl.handle.net/2047/D20211318
Chicago Manual of Style (16th Edition):
Elia, Mimmo. “Measurement apparatus and modelling of laminar burning speed and mass burning rate of syngas and onset of auto-ignition of N-heptane and gas to liquid fuel.” 2016. Doctoral Dissertation, Northeastern University. Accessed January 22, 2021.
http://hdl.handle.net/2047/D20211318.
MLA Handbook (7th Edition):
Elia, Mimmo. “Measurement apparatus and modelling of laminar burning speed and mass burning rate of syngas and onset of auto-ignition of N-heptane and gas to liquid fuel.” 2016. Web. 22 Jan 2021.
Vancouver:
Elia M. Measurement apparatus and modelling of laminar burning speed and mass burning rate of syngas and onset of auto-ignition of N-heptane and gas to liquid fuel. [Internet] [Doctoral dissertation]. Northeastern University; 2016. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/2047/D20211318.
Council of Science Editors:
Elia M. Measurement apparatus and modelling of laminar burning speed and mass burning rate of syngas and onset of auto-ignition of N-heptane and gas to liquid fuel. [Doctoral Dissertation]. Northeastern University; 2016. Available from: http://hdl.handle.net/2047/D20211318
University of New South Wales
9.
Chatakonda, Obulesu.
Large Eddy simulations of premixed turbulent combustion.
Degree: Photovoltaics & Renewable Energy Engineering, 2012, University of New South Wales
URL: http://handle.unsw.edu.au/1959.4/52790
;
https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11463/SOURCE01?view=true
► In the past two decades, Large-Eddy Simulation (LES) has become well established for modelling non-reacting flows. However, LES is still undergoing significant development for reacting…
(more)
▼ In the past two decades, Large-Eddy Simulation (LES) has become well established for modelling non-reacting flows. However, LES is still undergoing significant development for reacting flows. The mostchallenging topic in LES of combusting flows is modelling the reaction rate. To this end, several models have been proposed in the literature. Many of the models proposed so far are limited to corrugated flame (CF) regime. However, in many premixed
combustion applications both CF and thin reaction zone (TRZ) regimes exist. There is, therefore, a need for accurate and robust physical modelling of the reaction rate across different regimes of premixed flames. In this thesis, a new flame wrinkling model is proposed based on fractal geometry concept requiring the modelling of an inner cut-off scale and fractal dimension. Damk¨ohler’s limiting scaling laws are usedto infer the cut-off and fractal dimension in limiting regimes. The assumptions made to obtain the fractal dimension in the proposed model are tested by analysing fractal characteristics of several thermochemical and thermo-nuclear direct numerical simulation (DNS) data sets featuring Damk¨ohler numbers. The fractal dimension is found to vary between 2.1 to 2.7 in the thermo-chemical hydrogen air turbulent premixed flames. The thermo-nuclear supernovae flames, which are in distributed regimes of
combustion, yield fractal dimension about 2.7. The results for the maximum fractal dimensions are higher than previously reported in the literature and can be explained theoretically by a Reynolds number similarity argument which shows that the limiting value of the fractal dimension at low Damk¨ohler number is 8/3.To assess the performance of the new proposed model and also the models reported in the literature, a priori analysis of two DNS data sets are used. The sub-grid models are assessed using constant coefficient and dynamic coefficient versions using an approximate Germano identity. The effects of filter size on the performance of the models are also investigated. A priori assessments of the models show very good results for the models having power law form for all DNS data and filter sizes. In addition to this, a posteriori tests are conducted to assess these models in a slot Bunsen burner configuration in the TRZ regime. A combined progress variable and level set model has been used to model reaction rate. Chemistry is obtained from tabulated chemistry by solving strained and unstrained flamelets. The comparison of a priori and a posteriori results with the DNS data provides strong support for the validity of the proposed model.
Advisors/Committee Members: Hawkes, Evatt, Photovoltaics & Renewable Energy Engineering, Faculty of Engineering, UNSW, Kook, Shawn, Mechanical & Manufacturing Engineering, Faculty of Engineering, UNSW.
Subjects/Keywords: Sub grid flame speed; Large eddy simulation; Premixed turbulent combustion; Fractal flame speed; Direct numerical simulations
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APA (6th Edition):
Chatakonda, O. (2012). Large Eddy simulations of premixed turbulent combustion. (Doctoral Dissertation). University of New South Wales. Retrieved from http://handle.unsw.edu.au/1959.4/52790 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11463/SOURCE01?view=true
Chicago Manual of Style (16th Edition):
Chatakonda, Obulesu. “Large Eddy simulations of premixed turbulent combustion.” 2012. Doctoral Dissertation, University of New South Wales. Accessed January 22, 2021.
http://handle.unsw.edu.au/1959.4/52790 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11463/SOURCE01?view=true.
MLA Handbook (7th Edition):
Chatakonda, Obulesu. “Large Eddy simulations of premixed turbulent combustion.” 2012. Web. 22 Jan 2021.
Vancouver:
Chatakonda O. Large Eddy simulations of premixed turbulent combustion. [Internet] [Doctoral dissertation]. University of New South Wales; 2012. [cited 2021 Jan 22].
Available from: http://handle.unsw.edu.au/1959.4/52790 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11463/SOURCE01?view=true.
Council of Science Editors:
Chatakonda O. Large Eddy simulations of premixed turbulent combustion. [Doctoral Dissertation]. University of New South Wales; 2012. Available from: http://handle.unsw.edu.au/1959.4/52790 ; https://unsworks.unsw.edu.au/fapi/datastream/unsworks:11463/SOURCE01?view=true
10.
Xu, Da.
Thermal and hydrodynamic effects of nanosecond discharges in air and application to plasma-assisted combustion : Effets thermiques et hydrodynamiques des décharges nanosecondes et application à la combustion assistée par plasma.
Degree: Docteur es, Energétique, 2013, Châtenay-Malabry, Ecole centrale de Paris
URL: http://www.theses.fr/2013ECAP0076
► Les décharges Nanosecondes Répétitives Pulsées (NRP) sont de plus en plus utilisées dans diverses applications, en particulier dans la combustion assistée par plasma et le…
(more)
▼ Les décharges Nanosecondes Répétitives Pulsées (NRP) sont de plus en plus utilisées dans diverses applications, en particulier dans la combustion assistée par plasma et le contrôle d'écoulement aérodynamique. Tout d'abord, nous étudions les effets thermiques et hydrodynamiques d'une décharge NRP en utilisant des mesures de Schlieren rapide quantitatives et des analyses numériques dans l'air à la pression atmosphérique à 300 et 1000 K. Les images Schlieren résolues en temps montrent l'expansion du canal de gaz chauffé à partir de 50 ns après la décharge et la propagation d'ondes de choc à partir d'environs 500 ns. L'onde de choc change de forme cylindrique à sphérique après 3 µs. Nous analysons des images Schlieren enregistrées à partir de 50 nanosecondes à 3 microsecondes après la décharge. Des profils de densité de gaz simulés en coordonnées cylindriques 1-D sont utilisés pour reconstruire des images Schlieren numériques pour la comparaison avec les résultats expérimentaux. Nous proposons une méthode originale pour déterminer la température du gaz initial et la fraction de l'énergie transférée dans le chauffage rapide, en utilisant une comparaison des profils de contraste d'images obtenues à partir d'images Schlieren expérimentales et numériques. Les résultats montrent qu'une fraction importante de l'énergie électrique est convertie en chauffage du gaz en quelques dizaines de nanosecondes. Les valeurs vont de 25 % pour un champ électrique réduit de 164 Td dans l'air à 300 K à environ 75 % à 270 Td dans l'air à 1000 K. Celles-ci reflètent les processus de chauffage rapide par quenching dissociatif de N2(B,C) par l'oxygène moléculaire. Deuxièmement, nous fournissons une base de données pour tester la modélisation cinétique de l'allumage pauvre de mélange par les décharges NRP. Le rayon d'allumage initial, le développement du noyau d'allumage à des pressions jusqu'à 10 bar sont caractérisées. Les comparaisons avec un allumeur classique montrent que de meilleurs résultats sont obtenus avec des décharges NRP en termes de vitesse de propagation de la flamme, en particulier à haute pression, où la vitesse de flamme augmente jusqu'à 20% à 10 bar en raison de l'augmentation de plissement du front de flamme induit par les décharges NRP. Enfin, nous étudions la réponse dynamique d'une flamme à l'actionnement par les décharges NRP dans un brûleur 12-kW. Les résultats montrent une réduction significative (75%) de la hauteur de décollement de flamme après l'application des décharges NRP. Le mécanisme en jeu est l'entrainement des radicaux OH et de la chaleur produite par la décharge vers la couche de cisaillement de gaz frais entrant. Cette étude ouvre ainsi de nouvelles perspectives vers le contrôle des instabilités de combustion.
Nanosecond repetitively pulsed (NRP) discharges are being increasingly used in various applications, in particular in plasma-assisted combustion and aerodynamic flow control. First, we studied the thermal and hydrodynamic effects of NRP discharges using quantitative Schlieren measurements and…
Advisors/Committee Members: Laux, Christophe (thesis director).
Subjects/Keywords: Décharge nanoseconde; Vitesse de flamme; Combustion assistée par plasma; Nanosecond discharge; Flame speed; Plasma-assisted combustion
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APA ·
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APA (6th Edition):
Xu, D. (2013). Thermal and hydrodynamic effects of nanosecond discharges in air and application to plasma-assisted combustion : Effets thermiques et hydrodynamiques des décharges nanosecondes et application à la combustion assistée par plasma. (Doctoral Dissertation). Châtenay-Malabry, Ecole centrale de Paris. Retrieved from http://www.theses.fr/2013ECAP0076
Chicago Manual of Style (16th Edition):
Xu, Da. “Thermal and hydrodynamic effects of nanosecond discharges in air and application to plasma-assisted combustion : Effets thermiques et hydrodynamiques des décharges nanosecondes et application à la combustion assistée par plasma.” 2013. Doctoral Dissertation, Châtenay-Malabry, Ecole centrale de Paris. Accessed January 22, 2021.
http://www.theses.fr/2013ECAP0076.
MLA Handbook (7th Edition):
Xu, Da. “Thermal and hydrodynamic effects of nanosecond discharges in air and application to plasma-assisted combustion : Effets thermiques et hydrodynamiques des décharges nanosecondes et application à la combustion assistée par plasma.” 2013. Web. 22 Jan 2021.
Vancouver:
Xu D. Thermal and hydrodynamic effects of nanosecond discharges in air and application to plasma-assisted combustion : Effets thermiques et hydrodynamiques des décharges nanosecondes et application à la combustion assistée par plasma. [Internet] [Doctoral dissertation]. Châtenay-Malabry, Ecole centrale de Paris; 2013. [cited 2021 Jan 22].
Available from: http://www.theses.fr/2013ECAP0076.
Council of Science Editors:
Xu D. Thermal and hydrodynamic effects of nanosecond discharges in air and application to plasma-assisted combustion : Effets thermiques et hydrodynamiques des décharges nanosecondes et application à la combustion assistée par plasma. [Doctoral Dissertation]. Châtenay-Malabry, Ecole centrale de Paris; 2013. Available from: http://www.theses.fr/2013ECAP0076
Northeastern University
11.
Wang, Ziyu.
Measurement of laminar burning speed and flame instability study of syngas/oxygen/helium premixed flame.
Degree: MS, Department of Mechanical and Industrial Engineering, 2016, Northeastern University
URL: http://hdl.handle.net/2047/D20213215
► Synthesis gas also known as syngas, which is a mixture of hydrogen and carbon monoxide have been expected to play an important role in future…
(more)
▼ Synthesis gas also known as syngas, which is a mixture of hydrogen and carbon monoxide have been expected to play an important role in future energy demand. Research studies into understanding the knowledge of its fundamental thermo-physical properties, such as laminar burning speed, flame structure, etc. are extremely relevant in internal combustion engine, gas turbine combustor and power plant. The aim of this thesis is to measure laminar burning speed and study flame instability of syngas/oxygen/helium mixtures. Different methods of measurement of laminar burning speed have been discussed in this thesis. In present works, the experiments were conducted in a constant volume cylindrical chamber coupled with a Z-shaped Schlieren/shadowgraph system. Pressure rise data during the flame propagation was obtained through pressure transducers on the cylindrical chamber wall and was a primary input into the thermodynamic model used to measure the laminar burning speed. A high speed CMOS camera capable of taking pictures up to 40,000 frames per second can be used to determine the stability of the flames. A syngas with different hydrogen concentrations (5%, 10% and 25%) have been used in this experiment. The laminar burning speed and flame instability of spherically expanding flames of syngas with oxygen/helium have been studied over a wide range of equivalence ratios (0.6, 1, 2 and 3), initial mixture temperatures (298 K, 400 K and 480 K) and initial pressures (0.5 atm, 1 atm and 2 atm). Based on these initial conditions, laminar burning speed has been measured for temperatures ranging from 298 K to 650 K, pressures between 0.5 to 7.3 atmospheres and equivalence ratios ranging from 0.6 to 3.0. The flame instabilities have been observed during flame propagation and considered into hydrodynamic and diffusive-thermal effects. Helium increases the stability of flame, and it has larger heat capacity ratio (γ=1.67) than nitrogen (γ=1.40). Those are the reasons why helium was used instead of nitrogen to increase the range of laminar burning speed measurement that can be used for kinetic validation. Data shows that the laminar burning speed of oxygen/helium is also higher than oxygen/nitrogen from the results in this thesis.
Subjects/Keywords: laminar burning speed; schlieren photography; syngas; Flame; Flame stability; Synthesis gas; Combustion; Helium; Thermal properties; Combustion
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APA ·
Chicago ·
MLA ·
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Export
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Manager
APA (6th Edition):
Wang, Z. (2016). Measurement of laminar burning speed and flame instability study of syngas/oxygen/helium premixed flame. (Masters Thesis). Northeastern University. Retrieved from http://hdl.handle.net/2047/D20213215
Chicago Manual of Style (16th Edition):
Wang, Ziyu. “Measurement of laminar burning speed and flame instability study of syngas/oxygen/helium premixed flame.” 2016. Masters Thesis, Northeastern University. Accessed January 22, 2021.
http://hdl.handle.net/2047/D20213215.
MLA Handbook (7th Edition):
Wang, Ziyu. “Measurement of laminar burning speed and flame instability study of syngas/oxygen/helium premixed flame.” 2016. Web. 22 Jan 2021.
Vancouver:
Wang Z. Measurement of laminar burning speed and flame instability study of syngas/oxygen/helium premixed flame. [Internet] [Masters thesis]. Northeastern University; 2016. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/2047/D20213215.
Council of Science Editors:
Wang Z. Measurement of laminar burning speed and flame instability study of syngas/oxygen/helium premixed flame. [Masters Thesis]. Northeastern University; 2016. Available from: http://hdl.handle.net/2047/D20213215
12.
Lim, Kian Min.
DNS of inhomogeneous reactants premixed combustion.
Degree: PhD, 2015, University of Cambridge
URL: https://doi.org/10.17863/CAM.14088
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.646274
► The search for clean and efficient combustors is motivated by the increasingly stringent emissions regulations. New gas turbine engines are designed to operate under lean…
(more)
▼ The search for clean and efficient combustors is motivated by the increasingly stringent emissions regulations. New gas turbine engines are designed to operate under lean conditions with inhomogeneous reactants to ensure cleanliness and stability of the combustion. This ushers in a new mode of combustion, called the inhomogeneous reactants premixed combustion. The present study investigates the effects of inhomogeneous reactants on premixed combustion, specifically on the interactions of an initially planar flame with field of inhomogeneous reactants. Unsteady and unstrained laminar methane-air flames are studied in one- and two-dimensional simulations to investigate the effects of normally and tangentially (to the flame surface) stratified reactants. A three-dimensional DNS of turbulent inhomogeneous reactants premixed combustion is performed to extend the investigation into turbulent flames. The methaneair combustion is represented by a complex chemical reaction mechanism with 18 species and 68 steps. The flame surface density (FSD) and displacement speed S_d have been used as the framework to analyse the inhomogeneous reactants premixed flame. The flames are characterised by an isosurface of reaction progress variable. The unsteady flames are compared to the steady laminar unstrained reference case. An equivalence ratio dip is observed in all simulations and it can serve as a marker for the premixed flame. The dip is attributed to the preferential diffusion of carbon- and hydrogen- containing species. Hysteresis of S_d is observed in the unsteady and unstrained laminar flames that propagate into normally stratified reactants. Stoichiometric flames propagating into lean mixture have a larger S_d than lean flames propagating into stoichiometric mixtures. The cross-dissipation term contribution to S_d is small (~~10%) but its contribution to the hysteresis of S_d is not (~~50%). Differential propagation of the flame surface is observed in the laminar flame that propagates into tangentially stratified reactants. Stretch on the flame surface is induced by the differential propagation, which in turn increases the flame surface area.
Subjects/Keywords: 621.43; Inhomogeneous reactants premixed combustion; Premixed combustion; Direct numerical simulation (DNS); Progress variable; Flame surface density (FSD); Displacement speed
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APA ·
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MLA ·
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Export
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APA (6th Edition):
Lim, K. M. (2015). DNS of inhomogeneous reactants premixed combustion. (Doctoral Dissertation). University of Cambridge. Retrieved from https://doi.org/10.17863/CAM.14088 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.646274
Chicago Manual of Style (16th Edition):
Lim, Kian Min. “DNS of inhomogeneous reactants premixed combustion.” 2015. Doctoral Dissertation, University of Cambridge. Accessed January 22, 2021.
https://doi.org/10.17863/CAM.14088 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.646274.
MLA Handbook (7th Edition):
Lim, Kian Min. “DNS of inhomogeneous reactants premixed combustion.” 2015. Web. 22 Jan 2021.
Vancouver:
Lim KM. DNS of inhomogeneous reactants premixed combustion. [Internet] [Doctoral dissertation]. University of Cambridge; 2015. [cited 2021 Jan 22].
Available from: https://doi.org/10.17863/CAM.14088 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.646274.
Council of Science Editors:
Lim KM. DNS of inhomogeneous reactants premixed combustion. [Doctoral Dissertation]. University of Cambridge; 2015. Available from: https://doi.org/10.17863/CAM.14088 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.646274
University of Cambridge
13.
Lim, Kian Min.
DNS of inhomogeneous reactants premixed combustion.
Degree: PhD, 2015, University of Cambridge
URL: https://www.repository.cam.ac.uk/handle/1810/247342https://www.repository.cam.ac.uk/bitstream/1810/247342/2/license.txt
;
https://www.repository.cam.ac.uk/bitstream/1810/247342/3/Kian%20Min%20Lim%20Thesis.pdf.txt
;
https://www.repository.cam.ac.uk/bitstream/1810/247342/5/Kian%20Min%20Lim%20Thesis%20Abstract.pdf.txt
;
https://www.repository.cam.ac.uk/bitstream/1810/247342/6/Kian%20Min%20Lim%20Thesis%20Abstract.pdf.jpg
;
https://www.repository.cam.ac.uk/bitstream/1810/247342/7/Kian%20Min%20Lim%20Thesis.pdf.jpg
► The search for clean and efficient combustors is motivated by the increasingly stringent emissions regulations. New gas turbine engines are designed to operate under lean…
(more)
▼ The search for clean and efficient combustors is motivated by the increasingly stringent emissions regulations. New gas turbine engines are designed to operate under lean conditions with inhomogeneous reactants to ensure cleanliness and stability of the combustion. This ushers in a new mode of combustion, called the inhomogeneous reactants premixed combustion.
The present study investigates the effects of inhomogeneous reactants on premixed combustion, specifically on the interactions of an initially planar flame with field of inhomogeneous reactants. Unsteady and unstrained laminar methane-air flames are studied in one- and two-dimensional simulations to investigate the effects of normally and tangentially (to the flame surface) stratified reactants. A three-dimensional DNS of turbulent inhomogeneous reactants premixed combustion is performed to extend the investigation into turbulent flames. The methaneair combustion is represented by a complex chemical reaction mechanism with 18 species and 68 steps.
The flame surface density (FSD) and displacement speed S_d have been used as the framework to analyse the inhomogeneous reactants premixed flame. The flames are characterised by an isosurface of reaction progress variable. The unsteady flames are compared to the steady laminar unstrained reference case. An equivalence ratio dip is observed in all simulations and it can serve as a marker for the premixed flame. The dip is attributed to the preferential diffusion of carbon- and hydrogen- containing species.
Hysteresis of S_d is observed in the unsteady and unstrained laminar flames that propagate into normally stratified reactants. Stoichiometric flames propagating into lean mixture have a larger S_d than lean flames propagating into stoichiometric mixtures. The cross-dissipation term contribution to S_d is small (~~10%) but its contribution to the hysteresis of S_d is not (~~50%).
Differential propagation of the flame surface is observed in the laminar flame that propagates into tangentially stratified reactants. Stretch on the flame surface is induced by the differential propagation, which in turn increases the flame surface area.
Subjects/Keywords: Inhomogeneous reactants premixed combustion; Premixed combustion; Direct numerical simulation (DNS); Progress variable; Flame surface density (FSD); Displacement speed
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lim, K. M. (2015). DNS of inhomogeneous reactants premixed combustion. (Doctoral Dissertation). University of Cambridge. Retrieved from https://www.repository.cam.ac.uk/handle/1810/247342https://www.repository.cam.ac.uk/bitstream/1810/247342/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/247342/3/Kian%20Min%20Lim%20Thesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/247342/5/Kian%20Min%20Lim%20Thesis%20Abstract.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/247342/6/Kian%20Min%20Lim%20Thesis%20Abstract.pdf.jpg ; https://www.repository.cam.ac.uk/bitstream/1810/247342/7/Kian%20Min%20Lim%20Thesis.pdf.jpg
Chicago Manual of Style (16th Edition):
Lim, Kian Min. “DNS of inhomogeneous reactants premixed combustion.” 2015. Doctoral Dissertation, University of Cambridge. Accessed January 22, 2021.
https://www.repository.cam.ac.uk/handle/1810/247342https://www.repository.cam.ac.uk/bitstream/1810/247342/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/247342/3/Kian%20Min%20Lim%20Thesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/247342/5/Kian%20Min%20Lim%20Thesis%20Abstract.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/247342/6/Kian%20Min%20Lim%20Thesis%20Abstract.pdf.jpg ; https://www.repository.cam.ac.uk/bitstream/1810/247342/7/Kian%20Min%20Lim%20Thesis.pdf.jpg.
MLA Handbook (7th Edition):
Lim, Kian Min. “DNS of inhomogeneous reactants premixed combustion.” 2015. Web. 22 Jan 2021.
Vancouver:
Lim KM. DNS of inhomogeneous reactants premixed combustion. [Internet] [Doctoral dissertation]. University of Cambridge; 2015. [cited 2021 Jan 22].
Available from: https://www.repository.cam.ac.uk/handle/1810/247342https://www.repository.cam.ac.uk/bitstream/1810/247342/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/247342/3/Kian%20Min%20Lim%20Thesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/247342/5/Kian%20Min%20Lim%20Thesis%20Abstract.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/247342/6/Kian%20Min%20Lim%20Thesis%20Abstract.pdf.jpg ; https://www.repository.cam.ac.uk/bitstream/1810/247342/7/Kian%20Min%20Lim%20Thesis.pdf.jpg.
Council of Science Editors:
Lim KM. DNS of inhomogeneous reactants premixed combustion. [Doctoral Dissertation]. University of Cambridge; 2015. Available from: https://www.repository.cam.ac.uk/handle/1810/247342https://www.repository.cam.ac.uk/bitstream/1810/247342/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/247342/3/Kian%20Min%20Lim%20Thesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/247342/5/Kian%20Min%20Lim%20Thesis%20Abstract.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/247342/6/Kian%20Min%20Lim%20Thesis%20Abstract.pdf.jpg ; https://www.repository.cam.ac.uk/bitstream/1810/247342/7/Kian%20Min%20Lim%20Thesis.pdf.jpg
Michigan Technological University
14.
Pourhasanzadehsharifi, Mary.
STUDY OF SPARK DISCHARGE AND CYCLE-TO-CYCLE COMBUSTION VARIATIONS USING OPTICAL DIAGNOSTICS.
Degree: PhD, Department of Mechanical Engineering-Engineering Mechanics, 2020, Michigan Technological University
URL: https://digitalcommons.mtu.edu/etdr/1032
► Combustion plays a dominant role in power generation and transportation. In spark ignition (SI) engines, the combustion process is originated from an electrical discharge…
(more)
▼ Combustion plays a dominant role in power generation and transportation. In spark ignition (SI) engines, the
combustion process is originated from an electrical discharge within the spark plug electrodes. One important physical parameter affecting the spark discharge process and subsequent flame kernel propagation is the in-cylinder crossflow motion. Increasing the crossflow velocity generates turbulence in the
combustion chamber. This is attributed to the spark channel being elongated at higher crossflow velocities. A longer spark channel length contains a higher discharge voltage which can induce a new re-spark across the spark plug electrodes. Furthermore, a longer spark channel expands the spatial spark discharge volume, affecting the initial formation and propagation of the flame kernel. Understanding the flame evolution physics in the cylinder and the corresponding cyclic variability in the
combustion process under turbulent flows are of utmost importance to increasing efficiency of advanced engine technologies. In particular, knowledge of the cycle-to-cycle variations in
combustion could potentially improve engine efficiency and performance including fuel economy, driveability, and emissions. Therefore, the main goal of this research is to understand the effects of high-
speed crossflows on the initiation and development of the spark discharge and cyclic flame kernel propagation using optical diagnostics. Ignition tests are conducted in an optically accessible constant-volume spray and
combustion vessel under various high-
speed crossflows, pressures, and spark plug orientations to quantify the spark discharge process including the spark discharge channel, discharge duration, and glow discharge energy. Results show that increasing high-
speed crossflows shortens the discharge duration while the glow discharge energy increases. A correlation between the spark channel length and electrical measurements is provided. Furthermore, cyclic variability is studied in an optical SI engine with retarded ignition timing under stoichiometric conditions. A spark sweep and various in-cylinder tumble motions are performed to develop a fundamental understanding of the cyclic variability at different operating conditions. Here, optical diagnostics, in-cylinder pressure measurements, and ion signal waveforms are analyzed to quantify the cycle-to-cycle variations of candidate
combustion metrics including indicated mean effective pressure (IMEP) and mass fraction burned (MFB). Results provide a set of correlations among in-cylinder pressure measurements, ion signal data, and flame front data obtained from high-
speed combustion images. It is also found that the cyclic variability is amplified with retarding the spark timing.
Advisors/Committee Members: Jeffrey D. Naber, Seong-Young Lee.
Subjects/Keywords: constant-volume spray and combustion vessel; cycle-to-cycle variations; high-speed crossflow; optical engine; spark ignition engine; Heat Transfer, Combustion
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APA (6th Edition):
Pourhasanzadehsharifi, M. (2020). STUDY OF SPARK DISCHARGE AND CYCLE-TO-CYCLE COMBUSTION VARIATIONS USING OPTICAL DIAGNOSTICS. (Doctoral Dissertation). Michigan Technological University. Retrieved from https://digitalcommons.mtu.edu/etdr/1032
Chicago Manual of Style (16th Edition):
Pourhasanzadehsharifi, Mary. “STUDY OF SPARK DISCHARGE AND CYCLE-TO-CYCLE COMBUSTION VARIATIONS USING OPTICAL DIAGNOSTICS.” 2020. Doctoral Dissertation, Michigan Technological University. Accessed January 22, 2021.
https://digitalcommons.mtu.edu/etdr/1032.
MLA Handbook (7th Edition):
Pourhasanzadehsharifi, Mary. “STUDY OF SPARK DISCHARGE AND CYCLE-TO-CYCLE COMBUSTION VARIATIONS USING OPTICAL DIAGNOSTICS.” 2020. Web. 22 Jan 2021.
Vancouver:
Pourhasanzadehsharifi M. STUDY OF SPARK DISCHARGE AND CYCLE-TO-CYCLE COMBUSTION VARIATIONS USING OPTICAL DIAGNOSTICS. [Internet] [Doctoral dissertation]. Michigan Technological University; 2020. [cited 2021 Jan 22].
Available from: https://digitalcommons.mtu.edu/etdr/1032.
Council of Science Editors:
Pourhasanzadehsharifi M. STUDY OF SPARK DISCHARGE AND CYCLE-TO-CYCLE COMBUSTION VARIATIONS USING OPTICAL DIAGNOSTICS. [Doctoral Dissertation]. Michigan Technological University; 2020. Available from: https://digitalcommons.mtu.edu/etdr/1032
University of Kentucky
15.
Salem, Essa KH I J.
NUMERICAL SIMULATIONS OF PREMIXED FLAMES OF MULTI COMPONENT FUELS/AIR MIXTURES AND THEIR APPLICATIONS.
Degree: 2019, University of Kentucky
URL: https://uknowledge.uky.edu/me_etds/132
► Combustion has been used for a long time as a means of energy extraction. However, in the recent years there has been further increase in…
(more)
▼ Combustion has been used for a long time as a means of energy extraction. However, in the recent years there has been further increase in air pollution, through pollutants such as nitrogen oxides, acid rain etc. To solve this problem, there is a need to reduce carbon and nitrogen oxides through lean burning, fuel dilution and usage of bi-product fuel gases. A numerical analysis has been carried out to investigate the effectiveness of several reduced mechanisms, in terms of computational time and accuracy. The cases were tested for the combustion of hydrocarbons diluted with hydrogen, syngas, and bi-product fuel in a cylindrical combustor. The simulations were carried out using the ANSYS Fluent 19.1. By solving the conservations equations, several global reduced mechanisms (2-5-10 steps) were obtained. The reduced mechanisms were used in the simulations for a 2D cylindrical tube with dimensions of 40 cm in length and 2.0 cm diameter.
The mesh of the model included a proper fine quad mesh, within the first 7 cm of the tube and around the walls. By developing a proper boundary layer, several simulations were performed on hydrocarbon/air and syngas blends to visualize the flame characteristics. To validate the results “PREMIX and CHEMKIN†codes were used to calculate 1D premixed flame based on the temperature, composition of burned and unburned gas mixtures. Numerical calculations were carried for several hydrocarbons by changing the equivalence ratios (lean to rich) and adding small amounts of hydrogen into the fuel blends. The changes in temperature, radical formation, burning velocities and the reduction in NOx and CO2 emissions were observed. The results compared to experimental data to study the changes.
Once the results were within acceptable range, different fuels compositions were used for the premixed combustion through adding H2/CO/CO2 by volume and changing the equivalence ratios and preheat temperatures, in the fuel blends. The results on flame temperature, shape, burning velocity and concentrations of radicals and emissions were observed. The flame speed was calculated by finding the surface area of the flame, through the mass fractions of fuel components and products conversions that were simulated through the tube. The area method was applied to determine the flame speed. It was determined that the reduced mechanisms provided results within an acceptable range.
The variation of the inlet velocity had neglectable effects on the burning velocity. The highest temperatures were obtained in lean conditions (0.5-0.9) equivalence ratio and highest flame speed was obtained for Blast Furnace Gas (BFG) at elevated preheat temperature and methane-hydrogen fuels blends in the combustor.
The results included; reduction in CO2 and NOx emissions, expansion of the flammable limit, under the condition of having the same laminar flow. The usage of diluted natural gases, syngas and bi-product gases provides a step in solving environmental problems and providing efficient energy.
Subjects/Keywords: Premixed Combustion; Reduced Mechanisms; Flame Speed; Flame Structures; Radical Formation; Engineering; Heat Transfer, Combustion; Mechanical Engineering
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APA (6th Edition):
Salem, E. K. I. J. (2019). NUMERICAL SIMULATIONS OF PREMIXED FLAMES OF MULTI COMPONENT FUELS/AIR MIXTURES AND THEIR APPLICATIONS. (Masters Thesis). University of Kentucky. Retrieved from https://uknowledge.uky.edu/me_etds/132
Chicago Manual of Style (16th Edition):
Salem, Essa KH I J. “NUMERICAL SIMULATIONS OF PREMIXED FLAMES OF MULTI COMPONENT FUELS/AIR MIXTURES AND THEIR APPLICATIONS.” 2019. Masters Thesis, University of Kentucky. Accessed January 22, 2021.
https://uknowledge.uky.edu/me_etds/132.
MLA Handbook (7th Edition):
Salem, Essa KH I J. “NUMERICAL SIMULATIONS OF PREMIXED FLAMES OF MULTI COMPONENT FUELS/AIR MIXTURES AND THEIR APPLICATIONS.” 2019. Web. 22 Jan 2021.
Vancouver:
Salem EKIJ. NUMERICAL SIMULATIONS OF PREMIXED FLAMES OF MULTI COMPONENT FUELS/AIR MIXTURES AND THEIR APPLICATIONS. [Internet] [Masters thesis]. University of Kentucky; 2019. [cited 2021 Jan 22].
Available from: https://uknowledge.uky.edu/me_etds/132.
Council of Science Editors:
Salem EKIJ. NUMERICAL SIMULATIONS OF PREMIXED FLAMES OF MULTI COMPONENT FUELS/AIR MIXTURES AND THEIR APPLICATIONS. [Masters Thesis]. University of Kentucky; 2019. Available from: https://uknowledge.uky.edu/me_etds/132
Universidade do Rio Grande do Sul
16.
Haical, Rafael da Cruz.
Desenvolvimento de um sistema de controle de dinamômetro para testes de motores de combustão interna.
Degree: 2009, Universidade do Rio Grande do Sul
URL: http://hdl.handle.net/10183/17626
► Este trabalho aborda o desenvolvimento de um sistema de controle em malha fechada de torque e velocidade de rotação para testes de motores de combustão…
(more)
▼ Este trabalho aborda o desenvolvimento de um sistema de controle em malha fechada de torque e velocidade de rotação para testes de motores de combustão interna em uma bancada que possui um dinamômetro de correntes de Foucault. É apresentada uma revisão bibliográfica que abrange a fundamentação teórica básica sobre dinamômetro, alguns dos principais testes realizados em motores de combustão interna e técnicas de controle e instrumentação que estão sendo desenvolvidas por pesquisadores sobre o tema de controle de dinamômetro para testes de motores de combustão interna. O projeto surgiu com a necessidade do Laboratório de Motores da UFRGS realizar vários testes em motores a combustão tendo uma maior confiabilidade e rapidez para aquisição dos resultados. Este sistema está baseado num microcontrolador da famÃlia Atmega onde foram implementados os algoritmos de um controlador PID e um proporcional, que controlam respectivamente, os nÃveis de corrente contÃnua aplicadas no dinamômetro e o percentual de abertura da borboleta do motor combustão através de um motor de passo. A etapa de controle é executada no microcontrolador e uma interface gráfica foi implementada em Labview. Esta interface gráfica faz a leitura via porta serial dos dados do microcontrolador e traça suas curvas as salvando em arquivo, também se pode visualizar os sinais das temperaturas do motor e dinamômetro e nÃvel de combustÃvel do reservatório. A validação do controle desenvolvido foi comprovada através da verificação da convergência dos sinais para os valores de referência desejados. O controle propiciou também uma diminuição dos tempos para obtenção das respostas desejadas em comparação com o sistema anterior de controle manual.
This paper describes the development of a torque and rotation speed closed loop control system for internal combustion engine tests in a bench using a Foucault current dynamometer. A bibliographical review that encompasses basic dynamometer theoretical concepts, some of the most important tests applied to internal combustion engines, and control and instrumentation techniques currently under development on dynamometer testing for internal combustion engines is presented. This project needs to perform tests in combustion engines which would produce more dependable and faster results. The system herein developed is based on an Atmega-type microcontroller where algorithms of both a PID and a proportion controller, controlling respectively the levels of direct current applied through the dynamometer coils and the opening of an internal combustion engine throttle body by means of a step motor, were implemented. The control stage was done in the microcontroller and a graphic interface for a personal computer was created in Labview. This graphic interface facilitates the microcontroller data reading and traces its curves, saving them in a file; also, the engine and dynamometer temperature signals and the tank fuel level can be visualized. The validation of this control has been proved by the signal convergence check for desired…
Advisors/Committee Members: Perondi, Eduardo André.
Subjects/Keywords: Dynamometer; Motor de combustão interna; Dinamômetro; Speed control; Torque control; Instrumentation; Internal combustion engine
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APA (6th Edition):
Haical, R. d. C. (2009). Desenvolvimento de um sistema de controle de dinamômetro para testes de motores de combustão interna. (Thesis). Universidade do Rio Grande do Sul. Retrieved from http://hdl.handle.net/10183/17626
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):
Haical, Rafael da Cruz. “Desenvolvimento de um sistema de controle de dinamômetro para testes de motores de combustão interna.” 2009. Thesis, Universidade do Rio Grande do Sul. Accessed January 22, 2021.
http://hdl.handle.net/10183/17626.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Haical, Rafael da Cruz. “Desenvolvimento de um sistema de controle de dinamômetro para testes de motores de combustão interna.” 2009. Web. 22 Jan 2021.
Vancouver:
Haical RdC. Desenvolvimento de um sistema de controle de dinamômetro para testes de motores de combustão interna. [Internet] [Thesis]. Universidade do Rio Grande do Sul; 2009. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/10183/17626.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Haical RdC. Desenvolvimento de um sistema de controle de dinamômetro para testes de motores de combustão interna. [Thesis]. Universidade do Rio Grande do Sul; 2009. Available from: http://hdl.handle.net/10183/17626
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of California – Irvine
17.
Avila, Dimas.
Design and Verification of a Speed of Sound Sensor for Biogas for Future use in a Fuel Flexible Burner.
Degree: Mechanical and Aerospace Engineering, 2016, University of California – Irvine
URL: http://www.escholarship.org/uc/item/1zm7h760
► Due to strict emissions regulations, combustion systems in California are required to attain and maintain ultra-low emissions while achieving high efficiencies. Further, an increasing desire…
(more)
▼ Due to strict emissions regulations, combustion systems in California are required to attain and maintain ultra-low emissions while achieving high efficiencies. Further, an increasing desire to utilize fuels that are derived from renewable sources to help mitigate emission of greenhouse gases is requiring more flexibility of these systems. As a result, combustion systems are adopting an increasing array of sensors and controls to achieve the desired performance. The subject of this thesis is the development of a speed of sound (SOS) sensor for use in fuel flexible combustion systems. The goal is to facilitate the ability of the combustion system to self-tune to selected combustion characteristics, primarily the fuel stock. The fuel of primary interest is biogas, also known as digester gas, which is promoted by California’s energy policy as a renewable and carbon neutral fuel. In order to make such a system commercially available and help offset natural gas consumption with the underutilized fuel an inexpensive speed of sound sensor was developed to detect fuel compositions. The sensor was designed using acoustic attenuation models to select a suitable transducer for detection of the speed of sound. It was found that by detecting the speed of sound of a gas mixture up to two components from a gas mixture could be found. The model used to design the sensor was later verified by measuring the excitation of transmitting and receiving transducers in different digester gas mixtures. Utilizing this speed of sound sensor would help reach ultra-low NOX emissions while operating at lean conditions.
Subjects/Keywords: Mechanical engineering; Acoustic Attenuation; Biogas; Combustion; Dispersion Zone; Sensor; Speed of Sound
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APA (6th Edition):
Avila, D. (2016). Design and Verification of a Speed of Sound Sensor for Biogas for Future use in a Fuel Flexible Burner. (Thesis). University of California – Irvine. Retrieved from http://www.escholarship.org/uc/item/1zm7h760
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):
Avila, Dimas. “Design and Verification of a Speed of Sound Sensor for Biogas for Future use in a Fuel Flexible Burner.” 2016. Thesis, University of California – Irvine. Accessed January 22, 2021.
http://www.escholarship.org/uc/item/1zm7h760.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Avila, Dimas. “Design and Verification of a Speed of Sound Sensor for Biogas for Future use in a Fuel Flexible Burner.” 2016. Web. 22 Jan 2021.
Vancouver:
Avila D. Design and Verification of a Speed of Sound Sensor for Biogas for Future use in a Fuel Flexible Burner. [Internet] [Thesis]. University of California – Irvine; 2016. [cited 2021 Jan 22].
Available from: http://www.escholarship.org/uc/item/1zm7h760.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Avila D. Design and Verification of a Speed of Sound Sensor for Biogas for Future use in a Fuel Flexible Burner. [Thesis]. University of California – Irvine; 2016. Available from: http://www.escholarship.org/uc/item/1zm7h760
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Texas A&M University
18.
Morones Ruelas, Anibal.
Turbulence Measurements in a Fan-Stirred Flame Bomb Using Laser Doppler Velocimetry.
Degree: MS, Mechanical Engineering, 2015, Texas A&M University
URL: http://hdl.handle.net/1969.1/155689
► An ongoing project for the construction of a high-pressure, high-temperature turbulent flame speed vessel is furthered in this study. Prior to this work, a laminar…
(more)
▼ An ongoing project for the construction of a high-pressure, high-temperature turbulent flame
speed vessel is furthered in this study. Prior to this work, a laminar flame bomb apparatus was repurposed as a turbulent flame
speed vessel with the addition of four fans. Several impeller prototypes were proposed and tested in a mock model. The turbulence was characterized with PIV. At that time, homogenous and isotropic flow field and negligible mean flow were found at the plane of measurement, but the study was limited to a small area and one fan
speed.
The turbulence characterization is revisited here with a newly acquired LDV system. The study objectives are to: confirm the PIV measurements with LDV, this time in the actual vessel; expand the interrogation area from a plane to a 3d volume; asses the performance of the impellers at different levels rotational
speed, and; provide a more direct assessment of the temporal scale.
Basic concepts on the statistical description of turbulence were introduced. The LDV principle of operation and the function of the elements comprising the LDV system were explained.
The method developed for the experimentation was presented along with all the relevant parameters and adjustments in the control of the experiment. Two levels of fan
speed were chosen to run in the modified turbulent vessel, namely 8,000 and 12,000 rpm. A tridimensional space situated at the center of the vessel was systematically scanned and turbulence statistics were obtained.
The results confirmed some of the observations of the PIV, but the extension of the measurements to a tridimensional region also revealed unfavorable characteristics previously missed.
The work concludes suggesting improvements for a new design of turbulent flame bomb. In particular a new arrangement of the fans is advised.
Advisors/Committee Members: Petersen, Eric L (advisor), Morrison, Gerald L (committee member), Karpetis, Adonios N (committee member).
Subjects/Keywords: turbulent flame speed; fan-stirred flame bomb; LDV; turbulence; combustion; homogenous isotropic turbulence; pressure vessel
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APA (6th Edition):
Morones Ruelas, A. (2015). Turbulence Measurements in a Fan-Stirred Flame Bomb Using Laser Doppler Velocimetry. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/155689
Chicago Manual of Style (16th Edition):
Morones Ruelas, Anibal. “Turbulence Measurements in a Fan-Stirred Flame Bomb Using Laser Doppler Velocimetry.” 2015. Masters Thesis, Texas A&M University. Accessed January 22, 2021.
http://hdl.handle.net/1969.1/155689.
MLA Handbook (7th Edition):
Morones Ruelas, Anibal. “Turbulence Measurements in a Fan-Stirred Flame Bomb Using Laser Doppler Velocimetry.” 2015. Web. 22 Jan 2021.
Vancouver:
Morones Ruelas A. Turbulence Measurements in a Fan-Stirred Flame Bomb Using Laser Doppler Velocimetry. [Internet] [Masters thesis]. Texas A&M University; 2015. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/1969.1/155689.
Council of Science Editors:
Morones Ruelas A. Turbulence Measurements in a Fan-Stirred Flame Bomb Using Laser Doppler Velocimetry. [Masters Thesis]. Texas A&M University; 2015. Available from: http://hdl.handle.net/1969.1/155689
University of Toronto
19.
Syed, Wasi.
Conjugate Heat Transfer and Sooting Propensity of Ethanol for Laminar Coflow Diffusion Flames at Elevated Pressures.
Degree: 2017, University of Toronto
URL: http://hdl.handle.net/1807/79062
► The effect of sooting propensity of various compositions of methane and ethanol fuel in laminar diffusion flames at elevated pressures was analyzed numerically. Simulations of…
(more)
▼ The effect of sooting propensity of various compositions of methane and ethanol fuel in laminar diffusion flames at elevated pressures was analyzed numerically. Simulations of laminar diffusion flames comprised of pressure conditions up to 20 atm and composition of ethanol and methane fuel ranging from pure methane to pure ethanol. For all fuel compositions evaluated, the total carbon mass flow rate was maintained at a constant value of 0.458 mg/s. Soot formation and soot yield were corroborated against measured data and demonstrated well agreement with trends for pressure and fuel composition. For elevated pressure, fuel compositions with higher ethanol content yield higher peak soot concentrations, however at lower pressures synergistic effects result to soot concentration decreasing with ethanol content for ethanol dominant fuel mixtures. Finally, the effect of conjugate heat transfer and modification in burner wall geometry were evaluated which exhibited improved trends and overall results.
M.A.S.
Advisors/Committee Members: Groth, Clinton P. T., Aerospace Science and Engineering.
Subjects/Keywords: Combustion; Computational Fluid Dynamics (CFD); Emissions; Laminar Flame Speed; Soot; Temperature; 0538
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APA (6th Edition):
Syed, W. (2017). Conjugate Heat Transfer and Sooting Propensity of Ethanol for Laminar Coflow Diffusion Flames at Elevated Pressures. (Masters Thesis). University of Toronto. Retrieved from http://hdl.handle.net/1807/79062
Chicago Manual of Style (16th Edition):
Syed, Wasi. “Conjugate Heat Transfer and Sooting Propensity of Ethanol for Laminar Coflow Diffusion Flames at Elevated Pressures.” 2017. Masters Thesis, University of Toronto. Accessed January 22, 2021.
http://hdl.handle.net/1807/79062.
MLA Handbook (7th Edition):
Syed, Wasi. “Conjugate Heat Transfer and Sooting Propensity of Ethanol for Laminar Coflow Diffusion Flames at Elevated Pressures.” 2017. Web. 22 Jan 2021.
Vancouver:
Syed W. Conjugate Heat Transfer and Sooting Propensity of Ethanol for Laminar Coflow Diffusion Flames at Elevated Pressures. [Internet] [Masters thesis]. University of Toronto; 2017. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/1807/79062.
Council of Science Editors:
Syed W. Conjugate Heat Transfer and Sooting Propensity of Ethanol for Laminar Coflow Diffusion Flames at Elevated Pressures. [Masters Thesis]. University of Toronto; 2017. Available from: http://hdl.handle.net/1807/79062
Northeastern University
20.
Alhazmi, Bander Nafe.
Measurement of laminar burning speed and investigation of flame stability of syngas/air mixture.
Degree: MS, Department of Mechanical and Industrial Engineering, 2015, Northeastern University
URL: http://hdl.handle.net/2047/d20128903
► Synthetic gas (Syngas) is a growing alternative fuel for fossil fuel used in power generation industries. It is cost effective and friendly with the ecosystem.…
(more)
▼ Synthetic gas (Syngas) is a growing alternative fuel for fossil fuel used in power generation industries. It is cost effective and friendly with the ecosystem. In order to validate its capability as fuel supply, determination of syngas laminar burning speed is fundamental to understand its combustion behavior and kinetic model. Laminar burning speed of syngas with 5% of hydrogen and 95% carbon monoxide mixture has been measured using a constant volume cylindrical chamber and schlieren photography. The laminar burning speed has been measured in the range of temperature from 315 K to 490 K and range of pressure from 0.5 atm to 3.2 atm. The equivalence ratios for the combustible mixture ranged from 0.6 to 5. The thermodynamic model for calculating the laminar burning speed is based on the pressure rise method considering energy losses to the ignition source, unburned gas and chamber wall. The structure of the flame was studied through the shadowgraph method. Laminar burning speeds have only been reported for smooth flame. The results indicated that the laminar burning speed increases with increasing temperature and decreases as pressure increases. Flame cellularity was found to develop at early stage at high initial pressures. The measured burning speed has been compared with other researchersâ data and the results were in a good agreement.
Subjects/Keywords: burning; laminar; speed; syngas; Mechanical Engineering; Synthesis gas; Combustion; Measurement; Flame; Dynamics
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APA (6th Edition):
Alhazmi, B. N. (2015). Measurement of laminar burning speed and investigation of flame stability of syngas/air mixture. (Masters Thesis). Northeastern University. Retrieved from http://hdl.handle.net/2047/d20128903
Chicago Manual of Style (16th Edition):
Alhazmi, Bander Nafe. “Measurement of laminar burning speed and investigation of flame stability of syngas/air mixture.” 2015. Masters Thesis, Northeastern University. Accessed January 22, 2021.
http://hdl.handle.net/2047/d20128903.
MLA Handbook (7th Edition):
Alhazmi, Bander Nafe. “Measurement of laminar burning speed and investigation of flame stability of syngas/air mixture.” 2015. Web. 22 Jan 2021.
Vancouver:
Alhazmi BN. Measurement of laminar burning speed and investigation of flame stability of syngas/air mixture. [Internet] [Masters thesis]. Northeastern University; 2015. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/2047/d20128903.
Council of Science Editors:
Alhazmi BN. Measurement of laminar burning speed and investigation of flame stability of syngas/air mixture. [Masters Thesis]. Northeastern University; 2015. Available from: http://hdl.handle.net/2047/d20128903
Northeastern University
21.
Bennett, Casey Paul.
Laminar burning speed and flame structure of 1,1-difluoroethane (HFC-152a)/air and difluoromethane (HFC-32)/air mixtures.
Degree: MS, Department of Mechanical and Industrial Engineering, 2011, Northeastern University
URL: http://hdl.handle.net/2047/d20002134
► Of recent importance is the laminar burning speed of hydrofluorocarbons (HFCs) used in the refrigerant industry. Since the adoption of the Montreal Protocol in 1989…
(more)
▼ Of recent importance is the laminar burning speed of hydrofluorocarbons (HFCs) used in the refrigerant industry. Since the adoption of the Montreal Protocol in 1989 and the Kyoto Protocol in 1997 there has been an ongoing phase-out of chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) which deplete the ozone layer. Refrigerant companies are working to develop alternatives to CFC and HCFC based chemicals that have long been used in air conditioning and refrigeration systems. Alternatives that are currently in use include HFCs such as (HFC-134a); however HFC-134a has recently been deemed an environmental danger as well and will be phased out accordingly. Other HFCs with desirable thermodynamic properties are potential replacements but they are flammable and so the potential for ignition must be evaluated very carefully. The American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE) and the International Organization for Standardization (ISO) are finalizing a new international standard that specifies that laminar burning speed will be the parameter that classifies a chemical as being mildly flammable.; Laminar burning speed and flame structure of 1,1-difluroethane (HFC-152a)/air difluoromethane (HFC-32)/air mixtures has been studied. Experiments have been carried out in constant volume vessel coupled with a Schlieren/shadowgraph system and CMOS high speed camera capable of taking flame snapshots up to 40,000 frames per second. Laminar burning speed was determined using a thermodynamic model that employs the pressure rise history of the combustion process. Experiments were conducted for ambient initial conditions over a wide range of equivalence ratios. Laminar burning speed of HFC-152a/air mixtures has been measured for temperature range of 298 to 400 K and pressure range of 1.0 to 4.0 atm. Preliminary burning speeds of HFC32/air mixtures are discussed as is the impact of buoyant rise on measureing the burning speeds of slower burning mixtures. The effect of equivalence ratio on flame structure was also studied. The presence of hydrofluoric acid in the products of combustion was observed along with its effects on the experimental apparatus. The results of laminar burning speed have been compared with others in the literature. Recommendations are made for future measurements on fuel mixtures containing HFC samples.
Subjects/Keywords: burning; flame; HFC-152a; refrigerant; speed; velcocity; Heat Transfer, Combustion; Mechanical Engineering
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APA (6th Edition):
Bennett, C. P. (2011). Laminar burning speed and flame structure of 1,1-difluoroethane (HFC-152a)/air and difluoromethane (HFC-32)/air mixtures. (Masters Thesis). Northeastern University. Retrieved from http://hdl.handle.net/2047/d20002134
Chicago Manual of Style (16th Edition):
Bennett, Casey Paul. “Laminar burning speed and flame structure of 1,1-difluoroethane (HFC-152a)/air and difluoromethane (HFC-32)/air mixtures.” 2011. Masters Thesis, Northeastern University. Accessed January 22, 2021.
http://hdl.handle.net/2047/d20002134.
MLA Handbook (7th Edition):
Bennett, Casey Paul. “Laminar burning speed and flame structure of 1,1-difluoroethane (HFC-152a)/air and difluoromethane (HFC-32)/air mixtures.” 2011. Web. 22 Jan 2021.
Vancouver:
Bennett CP. Laminar burning speed and flame structure of 1,1-difluoroethane (HFC-152a)/air and difluoromethane (HFC-32)/air mixtures. [Internet] [Masters thesis]. Northeastern University; 2011. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/2047/d20002134.
Council of Science Editors:
Bennett CP. Laminar burning speed and flame structure of 1,1-difluoroethane (HFC-152a)/air and difluoromethane (HFC-32)/air mixtures. [Masters Thesis]. Northeastern University; 2011. Available from: http://hdl.handle.net/2047/d20002134
University of Lund
22.
Sigfrid, Ivan.
Investigation of a prototype industrial gas turbine
combustor using alternative gaseous fuels.
Degree: 2013, University of Lund
URL: https://lup.lub.lu.se/record/3972178
;
https://portal.research.lu.se/ws/files/3596764/3972217.pdf
► In this thesis, the effect of alternative gaseous fuels, with high hydrogen content and lower calorific value, on gas turbine combustion was investigated experimentally. The…
(more)
▼ In this thesis, the effect of alternative gaseous
fuels, with high hydrogen content and lower calorific value, on gas
turbine combustion was investigated experimentally. The aim of the
investigation was to find operational limitations for an
experimental burner and to supply data for validation of
computational fluid dynamics (CFD). Before examination of the
actual burner, the laminar flame speed was measured for a range of
gases. The measurement technique was based on Schlieren imaging
which is a measure of the density gradient through a flame surface.
A Bunsen type burner was used to measure the angle of a conical
flame from which the laminar flame speed was calculated. In order
to improve the comparability of these measurements with other
measurement methods the laminar flame speed was corrected for the
influence of stretch. The effect of stretch will increase or
decrease the flame speed depending on the curvature of the flame
and the physical properties of the gases involved in the
combustion, e.g. the Lewis number and preferential diffusivity. The
gas turbine burner examined was a downscaled version of the burner
that is now found in the commercial gas turbine, SGT-750. The
burner consists of three concentric sections. The central part is a
precombustor called rich-pilot-lean (RPL). The purpose of the RPL
is to supply heat and radicals to the other sections to stabilize
combustion. The next section is the Pilot, which serves as an
intermediate burner in which the equivalence ratio can be optimized
to stabilize combustion and minimize NOX emissions. The outermost
section is the Main. For the experimental burner approximately 79%
of the mass flow passes through this section. All sections have
their own swirlers that create recirculation zones for flame
stabilization. The experimental work in this thesis includes
measurements of the lean stability limit, emission optimization
(primarily NOX), flame diagnostic through OH-Laser induced
fluorescence (LIF) and particle image velocimetry (PIV). Tests were
conducted at both atmospheric conditions with preheated air (650 K)
and at elevated pressure up to 9 bar. Results from the experimental
investigations were also used to validate CFD computations using
reduced chemical kinetic schemes, and to validate reactor network
calculations based on perfectly stirred reactors (PSR) and plug
flow reactors (PFR). Lean stability limit experiments showed how
the RPL equivalence ratio could be optimized to lower the lean
blowout limit. Increasing the RPL equivalence ratio was shown to
extend the lean blowout limit, up to a limit after which the RPL
flame was quenched. Reactor network modelling showed that the
stabilizing effect of the RPL was a combination of thermal energy
and reactive radicals supplied to the flame zone. The important
radicals were shown to be H, O and OH. The emission optimization
measurements showed that lowering the equivalence ratio in both the
RPL and the pilot minimized the NOX emissions. CFD simulation
showed that the degree of mixing of both the RPL and the…
Subjects/Keywords: Energy Engineering; Combustion; Gas Turbine; Laminar flame speed; Stretch; Lean blowout; Emissions
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APA (6th Edition):
Sigfrid, I. (2013). Investigation of a prototype industrial gas turbine
combustor using alternative gaseous fuels. (Doctoral Dissertation). University of Lund. Retrieved from https://lup.lub.lu.se/record/3972178 ; https://portal.research.lu.se/ws/files/3596764/3972217.pdf
Chicago Manual of Style (16th Edition):
Sigfrid, Ivan. “Investigation of a prototype industrial gas turbine
combustor using alternative gaseous fuels.” 2013. Doctoral Dissertation, University of Lund. Accessed January 22, 2021.
https://lup.lub.lu.se/record/3972178 ; https://portal.research.lu.se/ws/files/3596764/3972217.pdf.
MLA Handbook (7th Edition):
Sigfrid, Ivan. “Investigation of a prototype industrial gas turbine
combustor using alternative gaseous fuels.” 2013. Web. 22 Jan 2021.
Vancouver:
Sigfrid I. Investigation of a prototype industrial gas turbine
combustor using alternative gaseous fuels. [Internet] [Doctoral dissertation]. University of Lund; 2013. [cited 2021 Jan 22].
Available from: https://lup.lub.lu.se/record/3972178 ; https://portal.research.lu.se/ws/files/3596764/3972217.pdf.
Council of Science Editors:
Sigfrid I. Investigation of a prototype industrial gas turbine
combustor using alternative gaseous fuels. [Doctoral Dissertation]. University of Lund; 2013. Available from: https://lup.lub.lu.se/record/3972178 ; https://portal.research.lu.se/ws/files/3596764/3972217.pdf
23.
Valencia Correa, Andres.
Etude expérimentale des concentrations de suie et des vitesses dans une flamme de paroi verticale : Experimental study of the concentrations of soot and speeds in a flame of vertical wall.
Degree: Docteur es, Physique, 2017, Normandie
URL: http://www.theses.fr/2017NORMR059
► La propagation d’un incendie dans un espace clos s’explique par l’inflammation de matières combustibles. Un cas important est celui de la propagation d’une flamme sur…
(more)
▼ La propagation d’un incendie dans un espace clos s’explique par l’inflammation de matières combustibles. Un cas important est celui de la propagation d’une flamme sur une paroi verticale. En effet si la flamme progresse dans le même sens que l’écoulement (cas co-courant), la croissance est rapide. Dans ce cas, l’émission des vapeurs combustibles (pyrolyse) et le dégagement de la chaleur apportée par la combustion sont couplés par les flux convectés et rayonnés à la paroi. Ces flammes de paroi verticale sont pilotées par les forces de flottabilité, et se caractérisent par un régime de basse vitesse et avec une forte production de suie. Bien que de nombreux travaux aient été consacrés à l’étude des flammes de paroi verticale [1-3], peu d’entre eux ont été dédiés à l’étude de l’écoulement dans la couche limite proche de la paroi et à l’étude des zones de production de suie, lesquels sont des données nécessaires pour la validation des codes de calcul. Pour cela, des mesures simultanées de vitesse par PIV et de concentration de suie par LII ont été réalisées sur un brûleur gaz en configuration paroi-verticale. Dans un premier temps, ces mesures ont permis l’analyse de la forme, de la taille et de la concentration des zones de formation de suies (poches de suie) à différentes hauteurs dans la flamme. Ensuite, les champs 2D de vitesses moyennes (horizontales et verticales) ont été étudiés, ainsi que leurs fluctuations (densités de probabilité et écart-type). Une description de la couche limite réactive, à l’aide d’une échelle caractéristique obtenue avec des mesures de vitesse plus résolues spatialement (PIV « zoomé »), a également été réalisée. Finalement, les mesures de LII et PIV couplées ont permis d’étudier l’influence du champ de vitesse sur la distribution des suies dans la flamme, ainsi que le transport et le flux turbulent de la fraction volumique de suie dans la couche limite réactive.
The fire growth and spread on a confined space depends on the inflammation and combustion of combustible materials. An important case is the fire propagation on a vertical wall configuration, in which the pyrolysis gas and the total heat flux released by the flame are coupled by convective and radiative heat flux from the flame to the wall. This kind of flame is piloted by the buoyancy forces, and is characterized by a low velocity regime and a strong generation of soot particles. Although numerous works have been devoted on the study of vertical wall flames, few have been carried out on the analysis of the flame within the reactive boundary layer and the study of the zones of production of soot particles, which is data necessary for fire simulation codes validation. In this aim, simultaneous measurements of velocity by Particle Image Velocity (PIV) and of soot volume fraction by planar laser induced incandescence (LII) have been carried out on vertical wall fire generated by a vertical porous burner fed with a CH4/C2H4 mixture. First, the characteristics of soot sheet (shape, size, thickness, and peak concentration) have been…
Advisors/Committee Members: Coppalle, Alexis (thesis director).
Subjects/Keywords: Combustion; Suies; Vitesse de flamme; Paroi verticale; PIV; Lasers; Incendies; Combustion; Soots; Flame speed; Particle Image Velocimetry; Lasers; Fire; Vertical wall; 628.92
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APA (6th Edition):
Valencia Correa, A. (2017). Etude expérimentale des concentrations de suie et des vitesses dans une flamme de paroi verticale : Experimental study of the concentrations of soot and speeds in a flame of vertical wall. (Doctoral Dissertation). Normandie. Retrieved from http://www.theses.fr/2017NORMR059
Chicago Manual of Style (16th Edition):
Valencia Correa, Andres. “Etude expérimentale des concentrations de suie et des vitesses dans une flamme de paroi verticale : Experimental study of the concentrations of soot and speeds in a flame of vertical wall.” 2017. Doctoral Dissertation, Normandie. Accessed January 22, 2021.
http://www.theses.fr/2017NORMR059.
MLA Handbook (7th Edition):
Valencia Correa, Andres. “Etude expérimentale des concentrations de suie et des vitesses dans une flamme de paroi verticale : Experimental study of the concentrations of soot and speeds in a flame of vertical wall.” 2017. Web. 22 Jan 2021.
Vancouver:
Valencia Correa A. Etude expérimentale des concentrations de suie et des vitesses dans une flamme de paroi verticale : Experimental study of the concentrations of soot and speeds in a flame of vertical wall. [Internet] [Doctoral dissertation]. Normandie; 2017. [cited 2021 Jan 22].
Available from: http://www.theses.fr/2017NORMR059.
Council of Science Editors:
Valencia Correa A. Etude expérimentale des concentrations de suie et des vitesses dans une flamme de paroi verticale : Experimental study of the concentrations of soot and speeds in a flame of vertical wall. [Doctoral Dissertation]. Normandie; 2017. Available from: http://www.theses.fr/2017NORMR059
INP Toulouse
24.
Rochette, Bastien.
Modeling and simulation of two-phase flow turbulent combustion in aeronautical engines : Modélisation et simulation de la combustion diphasique turbulente dans les moteurs aéronautiques.
Degree: Docteur es, Energétique et Transferts, 2019, INP Toulouse
URL: http://www.theses.fr/2019INPT0059
► De nos jours, plus de 80% de l'énergie consommée sur Terre provient de la combustion de combustibles fossiles. Des solutions alternatives à la combustion sont…
(more)
▼ De nos jours, plus de 80% de l'énergie consommée sur Terre provient de la combustion de combustibles fossiles. Des solutions alternatives à la combustion sont en cours de développement mais les contraintes spécifiques liées au transport aérien ne permettent pas actuellement d'alimenter des moteurs sans introduire de rupture technologique. Ces résultats expliquent les activités de recherche visant à améliorer les connaissances et le contrôle des processus de combustion afin de concevoir des moteurs aéronautiques plus propres et plus efficaces. Dans ce cadre, les Simulations aux Grandes Echelles ("Large Eddy Simulation" LES) sont devenues un outil puissant pour mieux comprendre les processus de combustion et les émissions de polluants. Cette thèse s'inscrit dans ce contexte et se focalise sur les modèles et stratégies de calcul afin de simuler avec plus de précision les écoulements réactifs turbulents gazeux et diphasiques dans la chambre de combustion des moteurs aéronautiques. Tout d'abord, une méthode générique et automatique pour la détection et l'épaississement du front de flamme a été développée pour le modèle TFLES, et validée pour plusieurs configurations académiques de complexité croissante. Cette approche générique est ensuite évaluée dans une simulation LES d'un brûleur de laboratoire et comparée à la méthode d'épaississement classique. Les résultats montrent un épaississement plus précis dans les régions post-flammes. Dans un second temps, à partir de l'analyse de flammes laminaires 1D diphasiques homogènes où la phase dispersée a une vitesse relative comparée à la phase porteuse, deux formulations analytiques pour la vitesse de propagation de ces flammes ont été proposées et validées. La concordance entre les vitesses de flammes mesurées et estimées démontre que le modèle et ses paramètres prennent correctement en compte les principaux mécanismes physiques contrôlant ces flammes diphasiques. Enfin, les modèles TFLES les plus récents ont été testés sur des configurations de flamme turbulente gazeuse/diphasique complexes. Les avantages et les inconvénients de ces modèles ont été étudiés afin de contribuer à la compréhension des mécanismes liés à la combustion turbulente et de proposer une stratégie de modélisation par LES pour améliorer la fidélité des simulations réactives
Nowadays, more than 80% of the energy consumed on Earth is produced by burning fossil fuels. Alternative solutions to combustion are being developed but the specific constraints related to air transport do not make it possible to currently power engines without introducing a technological breakthrough. These findings explain the research activity to improve the knowledge and the control of combustion processes to design cleaner, and more efficient aeronautical engines. In this framework, Large Eddy Simulations (LES) have become a powerful tool to better understand combustion processes and pollutant emissions. This PhD thesis is part of this context and focuses on the models and numerical strategies to simulate with more accuracy…
Advisors/Committee Members: Poinsot, Thierry (thesis director), Vermorel, Olivier (thesis director).
Subjects/Keywords: Combustion turbulente diphasique; Modèle de vitesse de flamme diphasique laminaire; Senseur de flamme générique; Two-phase turbulent combustion; Two-phase laminar flame speed model; Generic flame sensor
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APA (6th Edition):
Rochette, B. (2019). Modeling and simulation of two-phase flow turbulent combustion in aeronautical engines : Modélisation et simulation de la combustion diphasique turbulente dans les moteurs aéronautiques. (Doctoral Dissertation). INP Toulouse. Retrieved from http://www.theses.fr/2019INPT0059
Chicago Manual of Style (16th Edition):
Rochette, Bastien. “Modeling and simulation of two-phase flow turbulent combustion in aeronautical engines : Modélisation et simulation de la combustion diphasique turbulente dans les moteurs aéronautiques.” 2019. Doctoral Dissertation, INP Toulouse. Accessed January 22, 2021.
http://www.theses.fr/2019INPT0059.
MLA Handbook (7th Edition):
Rochette, Bastien. “Modeling and simulation of two-phase flow turbulent combustion in aeronautical engines : Modélisation et simulation de la combustion diphasique turbulente dans les moteurs aéronautiques.” 2019. Web. 22 Jan 2021.
Vancouver:
Rochette B. Modeling and simulation of two-phase flow turbulent combustion in aeronautical engines : Modélisation et simulation de la combustion diphasique turbulente dans les moteurs aéronautiques. [Internet] [Doctoral dissertation]. INP Toulouse; 2019. [cited 2021 Jan 22].
Available from: http://www.theses.fr/2019INPT0059.
Council of Science Editors:
Rochette B. Modeling and simulation of two-phase flow turbulent combustion in aeronautical engines : Modélisation et simulation de la combustion diphasique turbulente dans les moteurs aéronautiques. [Doctoral Dissertation]. INP Toulouse; 2019. Available from: http://www.theses.fr/2019INPT0059
Cornell University
25.
Sattler, Sandra.
Application of Crossed-Plane Tomography and Stereo Particle Image Velocimetry for Three-Dimensional Analysis of Premixed Turbulent Flames.
Degree: 2008, Cornell University
URL: http://hdl.handle.net/1813/10742
► Crossed-Plane Laser Tomography (CPLT) and similar laser imaging methods have been used to measure instantaneous flamelet surface normal vectors in premixed turbulent flames to study…
(more)
▼ Crossed-Plane Laser Tomography (CPLT) and similar laser imaging methods have been used to measure instantaneous flamelet surface normal vectors in premixed turbulent flames to study the wrinkling of flamelet surfaces and the internal structure of the flamelet. CPLT was applied to measure flamelet orientations of premixed turbulent V-flames with increasing downstream distance from the stabilizing rod. Also, a combined CPLT and Stereo Particle Image Velocimetry (SPIV) technique was developed to measure flamelet orientation statistics, three dimensional reactant velocities, and flamelet displacement speeds in a turbulent V-flame. This technique was also used to measure in-plane flamelet curvature in laboratory V-flames. The distribution of flamelet orientations is found to have a simple universal form depending on a single parameter, ?, for all flames studied to date. ? and AT/A, the mean flamelet area increase due to turbulence, grow linearly with distance from the stabilizer. The observed growth rates in ? and AT/A vary considerably from flame condition to flame condition, and the differences cannot be explained solely by changes in u?/SLo, the ratio of the turbulence intensity to the unstretched laminar flame speed.
Combined CPLT and SPIV are applied to measure three-dimensional flamelet orientation, reactant velocity, and flamelet displacement data in premixed turbulent flames. Three-dimensional flamelet orientation information is calculated from two simultaneous, orthogonal imaging measurements. Using SPIV, three-dimensional seed particle velocity measurements are obtained using two cameras. Each camera records an image pair separated by a short time interval and views the same region of the flame from a different perspective. Based on these different views of particle displacements corrected for thermophoretic effects, all three components of reactant velocity are found. The combined CPLT and SPIV technique measured instantaneous, three-dimensional flamelet orientation, flamelet surface curvature and the flamelet displacement speed, defined as the component of the relative velocity between the reactants and the flame surface that is normal to the surface. Displacement speed data showed both a broad distribution of values and a significant probability of negative values. The breadth of the distribution and the presence of negative displacement speeds are attributed to high values of curvature and extensive tangential strain.
Subjects/Keywords: turbulent combustion; premixed flames; laser diagnostics; flame displacement speed
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APA (6th Edition):
Sattler, S. (2008). Application of Crossed-Plane Tomography and Stereo Particle Image Velocimetry for Three-Dimensional Analysis of Premixed Turbulent Flames. (Thesis). Cornell University. Retrieved from http://hdl.handle.net/1813/10742
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):
Sattler, Sandra. “Application of Crossed-Plane Tomography and Stereo Particle Image Velocimetry for Three-Dimensional Analysis of Premixed Turbulent Flames.” 2008. Thesis, Cornell University. Accessed January 22, 2021.
http://hdl.handle.net/1813/10742.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Sattler, Sandra. “Application of Crossed-Plane Tomography and Stereo Particle Image Velocimetry for Three-Dimensional Analysis of Premixed Turbulent Flames.” 2008. Web. 22 Jan 2021.
Vancouver:
Sattler S. Application of Crossed-Plane Tomography and Stereo Particle Image Velocimetry for Three-Dimensional Analysis of Premixed Turbulent Flames. [Internet] [Thesis]. Cornell University; 2008. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/1813/10742.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Sattler S. Application of Crossed-Plane Tomography and Stereo Particle Image Velocimetry for Three-Dimensional Analysis of Premixed Turbulent Flames. [Thesis]. Cornell University; 2008. Available from: http://hdl.handle.net/1813/10742
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Brno University of Technology
26.
Vopršal, Oldřich.
StÅ™ednà efektivnà tlak spalovacÃch motorů automobilů a motocyklů: Brake mean effective pressure of an internal-combustion engine for passengers cars and motorcycles.
Degree: 2020, Brno University of Technology
URL: http://hdl.handle.net/11012/192157
► The aim of this work is to discuss the meaning, definition and mapping of the characteristics of the value of the mean effective pressure depending…
(more)
▼ The aim of this work is to discuss the meaning, definition and mapping of the characteristics of the value of the mean effective pressure depending on the historical development of internal
combustion engines of automobiles and motorcycles from the initial concepts to the current development. In this work I want to compare and evaluate the values of the mean effective pressure for non-supercharged and supercharged piston
combustion cars and motorcycles. Part of the work will be a graphical representation of the values of mean effective pressures and subsequent analysis and evaluation of the values against the design concept of the internal
combustion engine in the historical period. Furthermore, a description of the structural elements that contribute to the increase of the mean effective pressure.
Advisors/Committee Members: Drápal, LubomÃr (advisor), SvÃda, David (referee).
Subjects/Keywords: StÅ™ednà elektivnà tlak; zdvihový objem; výkon; otáÄky; spalovacà motor; Mean effective pressure; stroke volume of engine; power; speed; internal combustion engine
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APA (6th Edition):
VoprÅ¡al, O. (2020). StÅ™ednà efektivnà tlak spalovacÃch motorů automobilů a motocyklů: Brake mean effective pressure of an internal-combustion engine for passengers cars and motorcycles. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/192157
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):
VoprÅ¡al, OldÅ™ich. “StÅ™ednà efektivnà tlak spalovacÃch motorů automobilů a motocyklů: Brake mean effective pressure of an internal-combustion engine for passengers cars and motorcycles.” 2020. Thesis, Brno University of Technology. Accessed January 22, 2021.
http://hdl.handle.net/11012/192157.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
VoprÅ¡al, OldÅ™ich. “StÅ™ednà efektivnà tlak spalovacÃch motorů automobilů a motocyklů: Brake mean effective pressure of an internal-combustion engine for passengers cars and motorcycles.” 2020. Web. 22 Jan 2021.
Vancouver:
VoprÅ¡al O. StÅ™ednà efektivnà tlak spalovacÃch motorů automobilů a motocyklů: Brake mean effective pressure of an internal-combustion engine for passengers cars and motorcycles. [Internet] [Thesis]. Brno University of Technology; 2020. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/11012/192157.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
VoprÅ¡al O. StÅ™ednà efektivnà tlak spalovacÃch motorů automobilů a motocyklů: Brake mean effective pressure of an internal-combustion engine for passengers cars and motorcycles. [Thesis]. Brno University of Technology; 2020. Available from: http://hdl.handle.net/11012/192157
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
27.
和田, 陽å¸.
DME燃料 : 空気混åˆæ°—ã®ç«ç‚Žä¼æ’を用ã„ãŸæ¶ˆç‚Žè·é›¢ã®æ¸¬å®šã«é–¢ã™ã‚‹ç ”究 : Measurement of quenching distance using flame propagation of DME fuel-air mixtures.
Degree: 2006, Hosei University / 法政大å¦
URL: http://hdl.handle.net/10114/3520
Subjects/Keywords: DME Pre-mixed combustion; Quenching distance; Flame propagation speed
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Manager
APA (6th Edition):
和田, é. (2006). DME燃料 : 空気混åˆæ°—ã®ç«ç‚Žä¼æ’を用ã„ãŸæ¶ˆç‚Žè·é›¢ã®æ¸¬å®šã«é–¢ã™ã‚‹ç ”究 : Measurement of quenching distance using flame propagation of DME fuel-air mixtures. (Thesis). Hosei University / 法政大å¦. Retrieved from http://hdl.handle.net/10114/3520
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):
和田, 陽å¸. “DME燃料 : 空気混åˆæ°—ã®ç«ç‚Žä¼æ’を用ã„ãŸæ¶ˆç‚Žè·é›¢ã®æ¸¬å®šã«é–¢ã™ã‚‹ç ”究 : Measurement of quenching distance using flame propagation of DME fuel-air mixtures.” 2006. Thesis, Hosei University / 法政大å¦. Accessed January 22, 2021.
http://hdl.handle.net/10114/3520.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
和田, 陽å¸. “DME燃料 : 空気混åˆæ°—ã®ç«ç‚Žä¼æ’を用ã„ãŸæ¶ˆç‚Žè·é›¢ã®æ¸¬å®šã«é–¢ã™ã‚‹ç ”究 : Measurement of quenching distance using flame propagation of DME fuel-air mixtures.” 2006. Web. 22 Jan 2021.
Vancouver:
和田 é. DME燃料 : 空気混åˆæ°—ã®ç«ç‚Žä¼æ’を用ã„ãŸæ¶ˆç‚Žè·é›¢ã®æ¸¬å®šã«é–¢ã™ã‚‹ç ”究 : Measurement of quenching distance using flame propagation of DME fuel-air mixtures. [Internet] [Thesis]. Hosei University / 法政大å¦; 2006. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/10114/3520.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
和田 é. DME燃料 : 空気混åˆæ°—ã®ç«ç‚Žä¼æ’を用ã„ãŸæ¶ˆç‚Žè·é›¢ã®æ¸¬å®šã«é–¢ã™ã‚‹ç ”究 : Measurement of quenching distance using flame propagation of DME fuel-air mixtures. [Thesis]. Hosei University / 法政大å¦; 2006. Available from: http://hdl.handle.net/10114/3520
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Oxford
28.
Hinton, Nathan Ian David.
Measuring laminar burning velocities using constant volume combustion vessel techniques.
Degree: PhD, 2014, University of Oxford
URL: http://ora.ox.ac.uk/objects/uuid:5b641b04-8040-4d49-a7e8-aae0b0ffc8b5
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.655109
► The laminar burning velocity is an important fundamental property of a fuel-air mixture at given conditions of temperature and pressure. Knowledge of burning velocities is…
(more)
▼ The laminar burning velocity is an important fundamental property of a fuel-air mixture at given conditions of temperature and pressure. Knowledge of burning velocities is required as an input for combustion models, including engine simulations, and the validation of chemical kinetic mechanisms. It is also important to understand the effect of stretch upon laminar flames, to correct for stretch and determine true (unstretched) laminar burning velocities, but also for modelling combustion where stretch rates are high, such as turbulent combustion models. A constant volume combustion vessel has been used in this work to determine burning velocities using two methods: a) flame speed measurements during the constant pressure period, and b) analysis of the pressure rise data. Consistency between these two techniques has been demonstrated for the first time. Flame front imaging and linear extrapolation of flame speed has been used to determine unstretched flame speeds at constant pressure and burned gas Markstein lengths. Measurement of the pressure rise during constant volume combustion has been used along with a numerical multi-zone combustion model to determine burning velocities for elevated temperatures and pressures as the unburned gas ahead of the spherically expanding flame front is compressed isentropically. This burning velocity data is correlated using a 14 term correlation to account for the effects of equivalence ratio, temperature, pressure and fraction of diluents. This correlation has been modified from an existing 12 term correlation to more accurately represent the dependence of burning velocity upon temperature and pressure. A number of fuels have been tested in the combustion vessel. Biogas (mixtures of CH4 and CO2) has been tested for a range of equivalence ratios (0.7–1.4), with initial temperatures of 298, 380 and 450 K, initial pressures of 1, 2 and 4 bar and CO2 fractions of up to 40% by mole. Hydrous ethanol has been tested at the same conditions (apart from 298 K due to the need to vaporise the ethanol), and for fractions of water up to 40% by volume. Binary, ternary and quaternary blends of toluene, n-heptane, ethanol and iso-octane (THEO) have been tested for stoichiometric mixtures only, at 380 and 450 K, and 1, 2 and 4 bar, to represent surrogate gasoline blended with ethanol. For all fuels, correlation coefficients have been obtained to represent the burning velocities over wide ranging conditions. Common trends are seen, such as the reduction in burning velocity with pressure and increase with temperature. In the case of biogas, increasing CO2 results in a decrease in burning velocity, a shift in peak burning velocity towards stoichiometric, a decrease in burned gas Markstein length and a delayed onset of cellularity. For hydrous ethanol the reduction in burning velocity as H2O content is increased is more noticeably non-linear, and whilst the onset of cellularity is delayed, the effect on Markstein length is minor.…
Subjects/Keywords: 621.4; Engineering & allied sciences; Combustion; fuels; premixed flames; burning velocity; flame speed; flame stretch; biogas; hydrous ethanol
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Manager
APA (6th Edition):
Hinton, N. I. D. (2014). Measuring laminar burning velocities using constant volume combustion vessel techniques. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:5b641b04-8040-4d49-a7e8-aae0b0ffc8b5 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.655109
Chicago Manual of Style (16th Edition):
Hinton, Nathan Ian David. “Measuring laminar burning velocities using constant volume combustion vessel techniques.” 2014. Doctoral Dissertation, University of Oxford. Accessed January 22, 2021.
http://ora.ox.ac.uk/objects/uuid:5b641b04-8040-4d49-a7e8-aae0b0ffc8b5 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.655109.
MLA Handbook (7th Edition):
Hinton, Nathan Ian David. “Measuring laminar burning velocities using constant volume combustion vessel techniques.” 2014. Web. 22 Jan 2021.
Vancouver:
Hinton NID. Measuring laminar burning velocities using constant volume combustion vessel techniques. [Internet] [Doctoral dissertation]. University of Oxford; 2014. [cited 2021 Jan 22].
Available from: http://ora.ox.ac.uk/objects/uuid:5b641b04-8040-4d49-a7e8-aae0b0ffc8b5 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.655109.
Council of Science Editors:
Hinton NID. Measuring laminar burning velocities using constant volume combustion vessel techniques. [Doctoral Dissertation]. University of Oxford; 2014. Available from: http://ora.ox.ac.uk/objects/uuid:5b641b04-8040-4d49-a7e8-aae0b0ffc8b5 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.655109
29.
Marashi, Seyedeh Sepideh.
Network Modeling Application to Laminar Flame Speed and NOx Prediction in Industrial Gas Turbines.
Degree: The Institute of Technology, 2013, Linköping UniversityLinköping University
URL: http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-113708
► The arising environmental concerns make emission reduction from combustion devices one of the greatest challenges of the century. Modern dry low-NOx emission combustion systems…
(more)
▼ The arising environmental concerns make emission reduction from combustion devices one of the greatest challenges of the century. Modern dry low-NOx emission combustion systems often operate under lean premixed turbulent conditions. In order to design and operate these systems efficiently, it is necessary to have a thorough understanding of combustion process in these devices. In premixed combustion, flame speed determines the conversion rate of fuel. The flame speed under highly turbulent conditions is defined as turbulent flame speed. Turbulent flame speed depends on laminar flame speed, which is a property of the combustible mixture. The goal of this thesis is to estimate laminar flame speed and NOx emissions under certain conditions for specific industrial gas turbines. For this purpose, an in-house one-dimensional code, GENE-AC, is used. At first, a data validation is performed in order to select an optimized chemical reaction mechanism which can be used safely with the fuels of interest in gas turbines. Results show that GRI-Mech 3.0 performs well in most cases. This mechanism is selected for further simulations. Secondly, laminar flame speed is calculated using GRI-Mech 3.0 at SGT-800 conditions. Results show that at gas turbine conditions, increasing ambient temperature and fuel to air ratio enhances flame speed, mainly due to faster reaction rates. Moreover, laminar flame speed is highly affected by fuel composition. In particular, adding hydrogen to a fuel changes chemical processes significantly, because hydrogen is relatively light and highly diffusive. Calculations are conducted over a range of equivalence ratios and hydrogen fractions in methane at atmospheric as well as gas turbine operating conditions. Results reveal some trends for changes in laminar flame speed, depending on hydrogen content in the mixture. The final part of the thesis involves the development of a reactor network model for the SGT-700 combustor in order to predict NOx emissions. The network model is built in GENE-AC based on results from available computational fluid dynamics (CFD) simulations of the combustor. The model is developed for full load conditions with variable pilot fuel ratios. The NOx emissions are predicted using GRI-Mech 3.0 mechanism. A parametric study shows the dependency of NOx emissions on equivalence ratio and residence time. For SGT-700 running on natural gas, NOx emissions are fitted to measurement data by tuning equivalence ratio and residence time. The model is then tested for a range of ambient temperatures and fuel compositions. It is found that, although the model can correctly predict the trends of ambient temperature and fuel effects on NOx emissions, these effects are to some extent over-estimated. Using future engine tests and amending calibration can improve the results.
Subjects/Keywords: Gas turbine; combustion; NOx; emissions; laminar flame speed; burning velocity; hydrogen; network modeling; reactor network modeling
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APA ·
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MLA ·
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APA (6th Edition):
Marashi, S. S. (2013). Network Modeling Application to Laminar Flame Speed and NOx Prediction in Industrial Gas Turbines. (Thesis). Linköping UniversityLinköping University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-113708
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):
Marashi, Seyedeh Sepideh. “Network Modeling Application to Laminar Flame Speed and NOx Prediction in Industrial Gas Turbines.” 2013. Thesis, Linköping UniversityLinköping University. Accessed January 22, 2021.
http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-113708.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Marashi, Seyedeh Sepideh. “Network Modeling Application to Laminar Flame Speed and NOx Prediction in Industrial Gas Turbines.” 2013. Web. 22 Jan 2021.
Vancouver:
Marashi SS. Network Modeling Application to Laminar Flame Speed and NOx Prediction in Industrial Gas Turbines. [Internet] [Thesis]. Linköping UniversityLinköping University; 2013. [cited 2021 Jan 22].
Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-113708.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Marashi SS. Network Modeling Application to Laminar Flame Speed and NOx Prediction in Industrial Gas Turbines. [Thesis]. Linköping UniversityLinköping University; 2013. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-113708
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
30.
Galle, Jonas.
Spray atomization of alternative fuels in medium speed diesel engines.
Degree: 2013, Ghent University
URL: http://hdl.handle.net/1854/LU-4216803
► Until today, the diesel engine is still the most important power source for heavy duty road & rail transport, marine, genset and agriculture applications. The…
(more)
▼ Until today, the diesel engine is still the most important power source for heavy duty road & rail transport, marine, genset and agriculture applications. The decreasing reserves of fossil fuels, the strict emission regulations, the greenhouse effect, the increasing energy demand and fuel prices are all strong drivers for research into the use of alternative fuels in internal
combustion engines. Potential alternative fuels for this application are straight vegetable oils and animal fats. Several manufacturers of medium
speed diesel engines show interest. However, due to the difference in fuel properties problems due to the lack of knowledge still exists and engine modifications are required. The study focused on the understanding of the behavior of the fuel during injection in the engine. This was realized through both experimental and numerical work. For the experimental work, a constant volume
combustion chamber, equipped with a medium
speed diesel injection system, was developed and baptized as the Ghent University
Combustion Chamber I (a.k.a. GUCCI). The setup allows the simulation of engine-like conditions and enables several optical diagnostics. Several boundary conditions were carefully analyzed and finally the influence of straight oil on the injection system and atomization were investigated in cold pressurized ambients. The numerical part consisted of the implementation of a spray model as sub-model for an engine simulation tool. The behavior of the model was evaluated for different commonly used diesel and biodiesel surrogates. The conclusions were used to make suggestions for oil surrogates. In a final step, the vaporizing spray model was validated with experiments that were conducted in the constant volume
combustion chamber at the Technical University of Eindhoven. The setup conditions were taken as determined by the internationally established engine
combustion network (ECN), making the results useful for comparison with similar setups and research at other institutions.
Advisors/Committee Members: Verhelst, Sebastian.
Subjects/Keywords: Technology and Engineering; GUCCI; constant volume combustion chamber; Straight oils; medium speed diesel engines; spray modeling
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APA ·
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Manager
APA (6th Edition):
Galle, J. (2013). Spray atomization of alternative fuels in medium speed diesel engines. (Thesis). Ghent University. Retrieved from http://hdl.handle.net/1854/LU-4216803
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):
Galle, Jonas. “Spray atomization of alternative fuels in medium speed diesel engines.” 2013. Thesis, Ghent University. Accessed January 22, 2021.
http://hdl.handle.net/1854/LU-4216803.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Galle, Jonas. “Spray atomization of alternative fuels in medium speed diesel engines.” 2013. Web. 22 Jan 2021.
Vancouver:
Galle J. Spray atomization of alternative fuels in medium speed diesel engines. [Internet] [Thesis]. Ghent University; 2013. [cited 2021 Jan 22].
Available from: http://hdl.handle.net/1854/LU-4216803.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Galle J. Spray atomization of alternative fuels in medium speed diesel engines. [Thesis]. Ghent University; 2013. Available from: http://hdl.handle.net/1854/LU-4216803
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
◁ [1] [2] [3] ▶
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Open Access Theses and Dissertations
