Academic literature on the topic 'Aeronautical turbine'
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Journal articles on the topic "Aeronautical turbine"
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Sarti Leme, Alexandre Domingos, Geraldo Creci, Edilson Rosa Barbosa de Jesus, Túlio César Rodrigues, and João Carlos Menezes. "Finite Element Analysis to Verify the Structural Integrity of an Aeronautical Gas Turbine Disc Made from Inconel 713LC Superalloy." Advanced Engineering Forum 32 (April 2019): 15–26. http://dx.doi.org/10.4028/www.scientific.net/aef.32.15.
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Gas turbines are very important because they can be used in several areas, such as aeronautics and electric power generation systems. The operation of a gas turbine can be done by less pollutant fuels when compared to traditional kerosene, for example, resulting in less degradation to environment. Gas turbines may fail from a variety of sources, with the possibility of serious damage results. In this work, the structural integrity of the hot disc of an aeronautical gas turbine is addressed. Several numerical analyses have been performed by the finite element method: Temperature Distributions, Thermal Stresses and Dilatations, Structural Stresses and Deformations, Modal Behaviors and Fatigue Analysis. Creep of blades has also been considered. These are the most important failure modes that can happen to the studied hot disc under operating service. All these analysis have been performed considering the boundary conditions at the design point with maximum rotational speed. The mesh of the problem has been strictly evaluated by adaptive refinement of nodes and elements combined with a convergence analysis of results. Then, the material and basic properties of the hot disc have been defined to assure a normal operation free from failures. Therefore, the mechanical drawings of the studied hot turbine disc have been released for manufacturing and the construction of the first prototype of the aeronautical gas turbine is in testing phase showing that the results presented in this work are consistent.
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Zhang, Bing, Jian-Guo Gao, Gui-Long Min, and Shoushuo Liu. "Reliability analysis of gear transmission system of aeronautical turbine starter under multi-constraint." Thermal Science 24, no. 3 Part A (2020): 1513–20. http://dx.doi.org/10.2298/tsci190517016z.
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At present, there are some problems in the reliability analysis method for gear transmission system of aeronautical turbine starter, such as low accuracy of finite element model, low efficiency of analysis and low accuracy of analysis results. To this end, a reliability analysis method for the gear transmission system of aeronautical turbine starter under multi-constraint is presented. A 3-D model of the gear pair of aeronautical turbine starter is constructed in UG. The model is input into the finite element software for meshing. The gear transmission of aeronautical turbine starter under working conditions is simulated by defining boundary conditions and applying loads, which provides a basis for reliability analysis of gear transmission system of aeronautical turbine starter. The reliability of the gear transmission system of the aeronautical turbine starter is evaluated by the comprehensive evaluation method, and the reliability of the system is evaluated by the contact of the evaluation results. According to the evaluation results, the reliability analysis of the gear transmission system of the aeronautical turbine starter is realized under the condition of multi-constraint. The experimental results show that the proposed method has high analysis efficiency and high analysis accuracy.
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Dunham, J. "50 years of turbomachinery research at Pyestock — part 2: turbines." Aeronautical Journal 104, no. 1034 (April 2000): 199–207. http://dx.doi.org/10.1017/s0001924000028104.
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Abstract The two parts of this paper summarise the turbomachinery research undertaken at Pyestock during the 50 years since the National Gas Turbine Establishment was formed in 1946. The theoretical and experimental activities are described, and their influence on UK military and civil aero engines is assessed. The way in which NGTE supported non-aeronautical gas turbines is also explained. Part 2 covers turbines.
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Dediu, Gabriel, and Daniel Eugeniu Crunteanu. "Automatic Control System for Gas Turbines Test Rig." Applied Mechanics and Materials 436 (October 2013): 398–405. http://dx.doi.org/10.4028/www.scientific.net/amm.436.398.
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The technical evolution of the industrial and aeronautical groups involving gas turbines, determined by the request of increased efficiency and reliability, imposes the control through modern command and control automation systems. The paper describes a system destined to safely monitor, command and control the working conditions through complete automation of all command functions of a gas turbine. The system is suitable for all series of applications involving gas turbines, also providing a decrease in exploitation and maintenance costs.
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Lemco, Ian. "Wittgenstein's aeronautical investigation." Notes and Records of the Royal Society 61, no. 1 (December 22, 2006): 39–51. http://dx.doi.org/10.1098/rsnr.2006.0163.
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After a rigorous German education in the physical sciences, young Ludwig Wittgenstein entered Manchester University as an aeronautical engineering research student. There he devised and patented a novel aero-engine employing an airscrew propeller driven by blade tip-jets. Within the context of the growth of English aviation during the first half of the twentieth century (including the contributions of many Fellows of the Royal Society) and taking into account related aspects of his life, this paper examines an unfulfilled engineering aspiration. In enlarging upon what Wittgenstein might have accomplished during his stay at Manchester, it contrasts his invention with later comparable proven designs, albeit applied to hybrid rotorcraft. His engine employed centrifugal flow compression and arguably was a precursor of Sir Frank Whittle's gas turbine. In conclusion, reasons are given for Wittgenstein's departure from Manchester.
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Dunham, J. "50 years of turbomachinery research at Pyestock — part one: compressors." Aeronautical Journal 104, no. 1033 (March 2000): 141–51. http://dx.doi.org/10.1017/s0001924000025331.
Full textAbstract:
Abstract The two parts of this paper summarise the turbomachinery research undertaken at Pyestock during the 50 years since the National Gas Turbine Establishment was formed in 1946. The theoretical and experimental activities are described, and their influence on UK military and civil aero engines is assessed. The way in which NGTE supported non-aeronautical gas turbines is also explained. Part one provides a general introduction and then covers compressors.
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Saenz-Aguirre, Aitor, Sergio Fernandez-Resines, Iñigo Aramendia, Unai Fernandez-Gamiz, Ekaitz Zulueta, Jose Manuel Lopez-Guede, and Javier Sancho. "5 MW Wind Turbine Annual Energy Production Improvement by Flow Control Devices." Proceedings 2, no. 23 (November 6, 2018): 1452. http://dx.doi.org/10.3390/proceedings2231452.
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Several flow control devices have been studied in recent years. Majority of them were designed firstly for aeronautical purposes. At present many research is aimed to introduce these devices in wind turbines (WTs) in order to optimize their aerodynamic performance. The main goal of the present work is to analyze the influence of passive flow control devices, Vortex Generators and Gurney Flaps, on the Annual Energy Production (AEP) of a large Horizontal Axis Wind Turbine (HAWT). Consequently, BEM based calculations were performed in order to study their effect on the NREL offshore 5 MW Baseline Wind Turbine. Obtained results show an increment in the maximum value of the power coefficient, Cp_max, and a considerable improvement of the AEP.
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Bassi, Stefano, Matteo Scafe, Enrico Leoni, Claudio Mingazzini, Narayan Jatinder Bhatia, and Andrea Rossi. "Development of recyclable Fibre Metal Laminates (FML), their mechanical characterization and FE modelling, aiming at structural application in aeronautics." MATEC Web of Conferences 349 (2021): 01010. http://dx.doi.org/10.1051/matecconf/202134901010.
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This study concerns with the optimisation of a fibre-reinforced composite material ply book and application to an aeronautical component. The presented material solution is a recyclable FML (Fibre Metal Laminate). Recyclable and structural PMCs (Polymeric Matrix Composites) developed up-to now in ENEA had to be improved to satisfy the high-demanding fire characteristics requirements in aeronautics, particularly for the case considered in ongoing project FireMat (www.firemat.it), namely a turbine-bonnet production. FireMat project objective is the combination of weight reduction and fire resistance, maximizing the use C2C recyclable, secondary and biomass derived raw materials. Aluminium layers were introduced inside the lamination, to act as oxygen barriers and improve fire-retardancy. FML were obtained starting from a fire-retardant biobased resin, which was associated with aeronautical grade basalt-derived mineral fabric, processed in the form of a prepreg and then coupled with aluminium foils. FE modelling was based on performed mechanical characterization of the single layers and inter- layer adhesive strength of the ply stack: a composite sandwich structure (including aluminium honeycomb) was optimised.
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Fatsis, Antonios. "Performance Enhancement of One and Two-Shaft Industrial Turboshaft Engines Topped With Wave Rotors." International Journal of Turbo & Jet-Engines 35, no. 2 (May 25, 2018): 137–47. http://dx.doi.org/10.1515/tjj-2016-0040.
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Abstract Wave rotors are rotating equipment designed to exchange energy between high and low enthalpy fluids by means of unsteady pressure waves. In turbomachinery, they can be used as topping devices to gas turbines aiming to improve performance. The integration of a wave rotor into a ground power unit is far more attractive than into an aeronautical application, since it is not accompanied by any inconvenience concerning the over-weight and extra dimensioning. Two are the most common types of ground industrial gas turbines: The one-shaft and the two-shaft engines. Cycle analysis for both types of gas turbine engines topped with a four-port wave rotor is calculated and their performance is compared to the performance of the baseline engine accordingly. It is concluded that important benefits are obtained in terms of specific work and specific fuel consumption, especially compared to baseline engines with low compressor pressure ratio and low turbine inlet temperature.
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Brookes, Stephen Peter, Hans Joachim Kühn, Birgit Skrotzki, Hellmuth Klingelhöffer, Rainer Sievert, Janine Pfetzing, Dennis Peter, and Gunther F. Eggeler. "Multi-Axial Thermo-Mechanical Fatigue of a Near-Gamma TiAl-Alloy." Advanced Materials Research 59 (December 2008): 283–87. http://dx.doi.org/10.4028/www.scientific.net/amr.59.283.
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A material family to replace the current superalloys in aeronautical gas turbine engines is considered to be that of gamma Titanium Aluminide (-TiAl) alloys. Structural components in aeronautical gas turbine engines typically experience large variations in temperatures and multiaxial states of stress under non-isothermal conditions. The uniaxial, torsional and bi-axial thermo-mechanical fatigue (TMF) behaviour of this -TiAl alloy have been examined at 400 – 800oC with strain amplitudes from 0.15% to 0.7%. The tests were conducted at both in-phase (IP) and out-of-phase (OP). The effects of TMF on the microstructure were also investigated. For the same equivalent mechanical strain amplitude uniaxial IP tests showed significantly longer lifetimes than pure torsional TMF tests. The non-proportional multiaxial OP test showed the lowest lifetimes at the same equivalent mechanical strain amplitude compared to the other types of tests.
Dissertations / Theses on the topic "Aeronautical turbine"
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Koupper, Charlie. "Unsteady multi-component simulations dedicated to the impact of the combustion chamber on the turbine of aeronautical gas turbines." Phd thesis, Toulouse, INPT, 2015. http://oatao.univ-toulouse.fr/14187/1/koupper_partie_1_sur_2.pdf.
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De nos jours, seules les turbines à gaz sont à même de propulser les larges aéronefs (avions ou hélicoptères). Depuis les premiers prototypes construits dans les années 40, l’efficacité et la puissance de ces moteurs n’ont cessé de s’améliorer. Chaque composant atteint de tels niveaux de performance que seules une rupture technologique ou un investissement conséquent peuvent permettre de repousser les limites d’efficacité d’une turbine à gaz. Une solution alternative peut être trouvée en constatant qu’un moteur est un système intégré complexe dans lequel tous les composants interagissent entre eux, affectant les performances de chaque module en comparaison de leur fonctionnement isolé. Avec la compacité croissante des turbines à gaz, ces interactions entre modules du moteur sont clairement renforcées et leur étude constitue une potentielle source de gain en termes de performance globale du moteur. Dans ce contexte, l’interface du moteur la plus critique est aujourd’hui la connexion entre la chambre de combustion et la turbine, qui présente les niveaux de pression, température et contraintes les plus élevés du moteur. L’objectif de cette thèse est d’améliorer la caractérisation actuelle de l’interface chambre- turbine afin de juger les méthodes de développement de cette interface et de concourir à l’amélioration des performances de la turbine et sa durée de vie. Pour ainsi faire, un nouveau simulateur de chambre non réactif, représentatif des architectures de chambres pauvres récentes, est développé dans le contexte du projet européen FACTOR (FP7). L’écoulement dans le module est analysé d’une part via le recours massif aux Simulations aux Grandes Echelles (LES), et d’autre part par une caractérisation expérimentale sur une version trisecteur du module, installée à l’Université de Florence (Italie). En tirant profit des complémentarités entre approche numérique et expérimentale, une base de données exhaustive est construite pour qualifier les simulations avancées et caractériser les quantités physiques à l’interface entre la chambre et la turbine. Des diagnostics avancés et des procédures de validation s’appuyant sur les riches données temporelles sont proposés dans l’objectif d’améliorer les processus de design de l’interface chambre-turbine. Par exemple, il est montré qu’il est parfois possible et nécessaire d’aller au-delà d’une simple analyse des moyennes et variances pour qualifier les prédictions à cette interface. Pour approfondir l’étude de l’interaction chambre-turbine, des simulations LES comprenant à la fois le simulateur de chambre et une paire de stators de la turbine haute pression sont réalisées. Ces prédictions purement numériques mettent en évidence l’effet potentiel induit par la présence des stators ainsi que l’influence du calage angulaire par rapport aux injecteurs. Ce dernier ensemble de simulations souligne la difficulté de proprement appréhender l’interface chambre-turbine, mais confirme qu’il peut être simulé par une approche LES à l’avenir.
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Al-Khudairi, Othman. "Structural performance of horizontal axis wind turbine blade." Thesis, Kingston University, 2014. http://eprints.kingston.ac.uk/32197/.
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The power output from a wind turbine is proportional to rotor swept area and as a result in the past 30 years continuous effort has been made to design larger blades. In this period, the blade length has been increased about 10 times since 1980s to present time. With the longest blade currently measuring more than 100m in length, wind turbine blade designers and manufacturers face enormous challenges to encounter the effect of increased weight and other loads on fatigue durability of the blade. Wind turbine blades are mainly made from glass fibre reinforced plastic (GFRP) composite. materials. As a result, in the design of various parts of wind turbine blades such as the shear web, spar cap and the aerofoil the fatigue behaviour of F RP materials is required. The performance of these parts as well as the adhesively bonded joint under fatigue loading is crucial for structural integrity of a long lasting blade. During operation, delamination can initiate and propagate shortening blade life; hence, characterisation of failure envelope of GFRP laminates under different loading mode is necessary. In this regard in this project, quasi-static tests were carried out to find mode 1, mode 11 and mixed mode I/11 delamination fracture toughness using DCB, ENF and MMB tests and the fracture envelope was established for various mode mixity. In the next stage, the stress-lifetime (S-N) diagrams of the GFRP was studied. Fatigue-life experiments on three different types of loading, i.e. tension-tension at R=0.1, 0.5, tension- compression at R=-1 and compression-compression at R=2 and R=10 were performed. From the results of S-N diagrams, the constant life diagrams (CLD) for 90 degree and 0 degree fibre directions were constructed. CLD diagrams are useful for prediction of fatigue lifetime for loading condition that no experimental data available. The analysis of delamination crack propagation under cyclic loading was next area of the research. The onset life and propagation delamination crack grth of 0//0 interface of GR P laminate in mode I loading using DCB specimens was investigated and the Gm. from the onset life test was determined. From the fitted curve to mode I experimental propagation data the Paris’ law coefficient for the laminated GFRP in mode I was determined. The mode II fatigue crack growth in laminated 0//0 GFRP material was also investigated using ENF specimens. The fatigue behaviour in this mode is analysed based on application of Paris’ law as a function of energy release rate for mode II loading. From the fitted curve to experimental data, the Paris’ law coefficient for the laminated GFRP in mode II was determined. The effect of fatigue delamination growth on fracture surface was studied by fractography analysis of SEM images of fracture surfaces. Studying the behaviour of GFRP under cyclic loading and delamination under static and dynamic load led to full-scale testing of wind turbine blade to establish damage tolerance of the blade under cyclic loading. The sensitivity of wind turbine blade to damage has considerable interest for turbine operators and manufacturers. For full-scale fatigue testing, calibration test and modal analysis of a 45.7m blade has been done and moment-strain diagram and natural frequencies of the blade were obtained. Next, the blade sensitivity to damage under fatigue loading was investigated. The blade has been damaged intentionally by initially inserting a crack of 0.2m between the shear web and spar cap and later it was extended to 1m. The effect of these damages on the modal shape, natural frequencies and strains at various locations of the blade were investigated. The damaged blade fatigue tested, the structural integrity and growth of damage were monitored, and the results were discussed. Finally for the improvement of delamination resistance for joints between spar beam and aero-shell stitching method was used. T-beam and box beam joint were chosen as the platform for testing the stitching effect on the delamination. Various pattern of stitching was applied and the optimum pattern was determined.
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Dupuy, Fabien. "Reduced Order Models and Large Eddy Simulation for Combustion Instabilities in aeronautical Gas Turbines." Thesis, Toulouse, INPT, 2020. http://www.theses.fr/2020INPT0046.
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Des réglementations de plus en plus strictes et un intérêt environnemental grandissant ont poussé les constructeurs de moteurs aéronautiques à développer la génération actuelle de chambres de combustion, affichant des consommations et émissions de polluants plus basses que jamais. Cependant, les phases de conception de chambres modernes ont clairement mis en évidence que celles-ci sont plus susceptibles de développer des instabilités de combustion, où le couplage entre l'acoustique de la chambre et la flamme suscite de larges oscillations de pression ainsi que des vibrations de la structure. Ces instabilités peuvent endommager le moteur, et potentiellement entraîner sa destruction. Dans le même temps, de considérables avancées ont eu lieu dans le domaine de la simulation numérique, et la Mécanique des Fluides Numérique (MFN) a démontré sa capacité à reproduire la dynamique de flammes instationnaires et les instabilités de combustion observées dans les moteurs. Pourtant, même avec le matériel informatique moderne, le temps de calcul reste la contrainte clé de ces simulations haute-fidélité, qui demeurent très coûteuses. Typiquement, couvrir la totalité du domaine de fonctionnement pour un moteur industriel est encore hors de portée. Des modèles dits bas-ordre existent également, et prédire efficacement les instabilités de combustion par leur intermédiaire est envisageable à la condition d'une modélisation appropriée de l'interaction entre l'acoustique et la flamme. La méthode de modélisation la plus commune de cet élément critique est la fonction de transfert de flamme (FTF) qui lie les fluctuations de taux de dégagement de chaleur aux fluctuations de vitesse en un point donné. Cette fonction de transfert peut être obtenue à partir de modèles analytiques, mais très peu existent pour des flammes swirlées turbulentes. Une autre approche consiste à réaliser des mesures expérimentales ou des simulations haute fidélité coûteuses, réduisant à néant la capacité de prédiction rapide recherchée avec les méthodes bas-ordre. Cette thèse vise donc à développer des outils bas ordre à la fois rapides et fiables pour la modélisation des instabilités de combustion, ainsi qu'à améliorer la compréhension des mécanismes inhérents à la réponse acoustique d'une flamme swirlée. A cet effet, une approche hybride nouvelle est proposée, où un nombre réduit de simulations haute fidélité peut être utilisé pour déterminer les paramètres d'entrée d'un modèle analytique représentatif de la fonction de transfert d'une flamme swirlée prémélangée. Le modèle analytique s'appuie sur des travaux antérieurs traitant la flamme comme une interface perturbée, et prend en compte la conversion acoustique-vorticité à travers un swirler. La validité du modèle est mise à l'épreuve en déterminant les divers paramètres nécessaires associés à partir de simulations numériques réactives stationnaires et pulsées d'une flamme prémélangée swirlée académique. Il est également démontré que le modèle peut prendre en compte diverses amplitudes de perturbation. Enfin, des simulations haute-fidélité 3D d'une turbine à gaz industrielle alimentée par un combustible liquide sont réalisées afin de déterminer s'il est possible de prédire numériquement un mode d'instabilité de combustion observé lors des essais. Pour cela, un ensemble de simulations forcées est mené à bien afin de souligner l'importance de l'acquisition de la réponse de la flamme diphasique, en comparant les positions de référence utilisées pour mesurer les vitesses fluctuantes ainsi que l'amplitude et l'origine de la perturbation acoustique. L'applicabilité du modèle analytique à ce cas complexe est aussi étudiée. Les résultats montrent que l'analyse acoustique proposée prédit bien la présence d'un mode instable, mais que le modèle bas ordre nécessite davantage de développements pour étendre son domaine de validité présuméIncreasingly stringent regulations as well as environmental concerns have lead gas turbine powered engine manufacturers to develop the current generation of combustors, which feature lower than ever fuel consumption and pollutant emissions. However, modern combustor designs have been shown to be prone to combustion instabilities, where the coupling between acoustics of the combustor and the flame results in large pressure oscillations and vibrations within the combustion chamber. These instabilities can cause structural damages to the engine or even lead to its destruction. At the same time, considerable developments have been achieved in the numerical simulation domain, and Computational Fluid Dynamics (CFD) has proven capable of capturing unsteady flame dynamics and combustion instabilities for aforementioned engines. Still, even with the current large and fast increasing computing capabilities, time remains the key constraint for these high fidelity yet computationally intensive calculations. Typically, covering the entire range of operating conditions for an industrial engine is still out of reach. In that respect, low order models exist and can be efficient at predicting the occurrence of combustion instabilities, provided an adequate modeling of the flame/acoustics interaction as appearing in the system is available. This essential piece of information is usually recast as the so called Flame Transfer Function (FTF) relating heat release rate fluctuations to velocity fluctuations at a given point. One way to obtain this transfer function is to rely on analytical models, but few exist for turbulent swirling flames. Another way consists in performing costly experiments or numerical simulations, negating the requested fast prediction capabilities. This thesis therefore aims at providing fast, yet reliable methods to allow for low order combustion instabilities modeling. In that context, understanding the underlying mechanisms of swirling flame acoustic response is also targeted. To address this issue, a novel hybrid approach is first proposed based on a reduced set of high fidelity simulations that can be used to determine input parameters of an analytical model used to express the FTF of premixed swirling flames. The analytical model builds on previous works starting with a level-set description of the flame front dynamics while also accounting for the acoustic-vorticity conversion through a swirler. For such a model, validation is obtained using reacting stationary and pulsed numerical simulations of a laboratory scale premixed swirl stabilized flame. The model is also shown to be able to handle various perturbation amplitudes. At last, 3D high fidelity simulations of an industrial gas turbine powered by a swirled spray flame are performed to determine whether a combustion instability observed in experiments can be predicted using numerical analysis. To do so, a series of forced simulations is carried out in en effort to highlight the importance of the two-phase flow flame response evaluation. In that case, sensitivity to reference velocity perturbation probing positions as well as the amplitude and location of the acoustic perturbation source are investigated. The analytical FTF model derived in the context of a laboratory premixed swirled burner is furthermore gauged in this complex case. Results show that the unstable mode is predicted by the acoustic analysis, but that the flame model proposed needs further improvements to extend its applicability range and thus provide data relevant to actual aero-engines
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Elfarra, Monier A. K. "Horizontal Axis Wind Turbine Rotor Blade: Winglet And Twist Aerodynamic Design And Optimization Using Cfd." Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12612987/index.pdf.
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The main purpose of this study is to aerodynamically design and optimize winglet, twist angle distribution and pitch angle for a wind turbine blade using CFD to produce more power. The RANS solver of Numeca Fine/Turbo was validated by two test cases, the NREL II and NREL VI blades. The results have shown a
considerable agreement with measurements for both cases. Two different preconditioners have been implemented for the low Mach number flow. The results have shown the superiority of Merkle preconditioner over Hakimi one and Merkle
was selected for further simulations. In addition to that, different turbulence models have been compared and the Launder &ndashSharma has shown the best agreement with measurements. Launder &ndash
Sharma was chosen for further simulations and for the design process. Before starting the design and optimization, different winglet configurations were studied. The winglets pointing towards the suction side of the blade have yielded higher power output. Genetic algorithm and artificial neural network were implemented in the design and optimization process. The optimized winglet has shown an increase in power of about 9.5 % where the optimized twist has yielded to an increase of 4%. Then the stall regulated blade has been converted into pitch regulated blade to yield more power output. The final design was produced by a combination of the optimized winglet, optimized twist andbest pitch angle for every wind speed. The final design has shown an increase in power output of about 38%.
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Effendy, Marwan. "Investigation of turbine blade trailing edge cooling and thermal mixing characteristics." Thesis, Kingston University, 2014. http://eprints.kingston.ac.uk/30604/.
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The present computation investigates a turbine blade with trailing-edge cutback coolant ejection designs, aiming for a comparison study of aerothermal performances such as discharge coefficient and film cooling effectiveness due to the change of trailing-edge geometries and blowing ratios. The shear-stress transport (SST) k-w turbulence model is adopted and numerical studies are carried out by two-stage investigations:- firstly, validation of an existing cutback blade model with staggered circular pin-fins array inside the cooling passage that has been extensively studied by other researchers and predicted internal passage discharge coefficient and film-cooling effectiveness along the cutback surface are compared to experimental measurements. RANS/URANS and DES are applied during this stage; secondly, further investigation of four main cases considering different key design parameters such as the ratio of lip thickness to slot height (t/H = 0.25, 0.5, 1.0 and 1.5), the design of internal features (i.e. circular pin-fin array, elliptic pin-fin array, and empty duct), the coolant ejection angle (alpha = 5 degrees, 10 degrees and 15 degrees). In addition, a trailing-edge cutback model with suction-side (SS) ─ pressure-side (PS) walls and lands is considered to create a more realistic blade design. The results show that both steady and unsteady RANS predictions are able to produce discharge coefficients in fairly good agreement with test data, but not the film-cooling effectiveness on cutback surfaces which over-predicts in far-field wake region. Further prediction improvements can be made by using unsteady DES approach. In terms of film-cooling effectiveness and shedding frequency, computational results indicate a strong dependency on those aforementioned key design parameters. This film-cooling effectiveness is strongly affected by turbulent flow structures along the cutback region, which is representing the dynamic mixing process between the mainstream flow and the ejecting coolant from the slot-exit. The use of elliptic pin-fin inside the cooling passage and thin lip thickness could improve the effectiveness of film-cooling. The increase of ejection angle yields almost near unity cooling effectiveness along the protected wall. Significant improvements on cooling performance are also achieved with higher blowing ratios. Computations of the trailing-edge cutback cooling with pressure-side (PS) and suction-side (SS) wall demonstrates that performance of the case without lands is better than that of the case with lands by discrepancy up to 18% in terms of overall-averaged film-cooling effectiveness. The blade trailing-edge design with lands causes a rapid decay of the averaged film-cooling effectiveness.
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Oksuz, Ozhan. "Multiploid Genetic Algorithms For Multi-objective Turbine Blade Aerodynamic Optimization." Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12609196/index.pdf.
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To decrease the computational cost of genetic algorithm optimizations,
surrogate models are used during optimization. Online update of surrogate
models and repeated exchange of surrogate models with exact model during
genetic optimization converts static optimization problems to dynamic ones.
However, genetic algorithms fail to converge to the global optimum in
dynamic optimization problems. To address these problems, a multiploid
genetic algorithm optimization method is proposed. Multi-fidelity surrogate
models are assigned to corresponding levels of fitness values to sustain the
static optimization problem. Low fidelity fitness values are used to decrease
the computational cost. The exact/highest-fidelity model fitness value is used for converging to the global optimum. The algorithm is applied to
single and multi-objective turbine blade aerodynamic optimization
problems. The design objectives are selected as maximizing the adiabatic
efficiency and torque so as to reduce the weight, size and the cost of the gas
turbine engine. A 3-D steady Reynolds-Averaged Navier-Stokes solver is
coupled with an automated unstructured grid generation tool. The solver is
validated by using two well known test cases. Blade geometry is modelled
by 37 design variables. Fine and coarse grid solutions are respected as high
and low fidelity surrogate models, respectively. One of the test cases is
selected as the baseline and is modified in the design process. The effects of
input parameters on the performance of the multiploid genetic algorithm are
studied. It is demonstrated that the proposed algorithm accelerates the
optimization cycle while providing convergence to the global optimum for
single and multi-objective problems.
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Akagi, Raymond. "Ram Air-Turbine of Minimum Drag." DigitalCommons@CalPoly, 2021. https://digitalcommons.calpoly.edu/theses/2261.
Full textAbstract:
The primary motivation for this work was to predict the conditions that would yield minimum drag for a small Ram-Air Turbine used to provide a specified power requirement for a small flight test instrument called the Boundary Layer Data System. Actuator Disk Theory was used to provide an analytical model for this work.
Classic Actuator Disk Theory (CADT) or Froude’s Momentum Theory was initially established for quasi-one-dimensional flows and inviscid fluids to predict the power output, drag, and efficiency of energy-extracting devices as a function of wake and freestream velocities using the laws of Conservations of Mass, Momentum, and Energy. Because swirl and losses due to the effects of viscosity have real and significant impacts on existing turbines, there is a strong motivation to develop models which can provide generalized results about the performance of an energy-extractor, such as a turbine, with the inclusion of these effects. A model with swirl and a model with losses due to the effects of viscosity were incorporated into CADT which yielded equations that predicted the performance of an energy-extractor for both un-ducted and ducted cases. In both of these models, for this application, additional performance parameters were analyzed including the drag, drag coefficient, power output, power coefficient, force coefficient, and relative efficiency.
For the un-ducted CADT, it is well known that the wake-to-freestream velocity ratio of 1/3 will give the maximum power extraction efficiency of 59.3%; this result is called the Betz limit. However, the present analysis shows that reduced drag for a desired power extraction will occur for wake-to-freestream velocity ratios higher than the value of 1/3 which results in maximum power extraction efficiency. This in turn means that a turbine with a larger area than the smallest possible turbine for a specified power extraction will actually experience a lower drag.
The model with the inclusion of swirl made use of the Moment of Momentum Theorem applied to a single-rotor actuator disk with no stators, in addition to the laws of Conservation of Mass, Momentum, and Energy from the CADT. The results from the model w/swirl showed that drag remains unchanged while power extracted decreases with the addition of swirl, with swirl effects becoming more severe for tip speed ratios below about 5. As for CADT, reduced drag for a specified power extraction can be achieved when the wake-to-freestream velocity ratio is higher that than which provides maximum power extraction efficiency. The model w/losses due to viscosity incorporated the losses into the Conservation of Energy relationship. The results from the model w/losses showed that there is a distinct wake-to-freestream velocity ratio at which minimum drag for a specified power output is achieved, and that this velocity ratio is usually—but not always—higher than that for which the power extraction efficiency is a maximum.
It was concluded that a lower drag for a specified power output of an energy-extractor can usually be achieved at a wake-to-freestream velocity ratio higher than that which produces the v maximum power extraction efficiency. The latter condition, known as the Betz limit for CADT, and which defines the minimum size for a turbine to provide a specified power extraction, is therefore not the correct target design condition to achieve lowest drag for a small Ram-Air Turbine to power BLDS.
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Notarianni, Gianmarco. "Analysis and modelling of the turbocharger behavior of an internal combustion engine for aeronautical application." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
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The goal of this thesis project is the creation and the validation of an estimation model developed for the prediction of the Wastegate valve behaviour, to define the splitting of mass flow rate between the turbine and the bypass valve in all the operative conditions of the turbocharger system, by an analysis of the experimental data obtained from tests performed in the engine test bench of the University.
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Gorgulu, Ilhan. "Numerical Simulation Of Turbine Internal Cooling And Conjugate Heat Transfer Problems With Rans-based Turbulance Models." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12615000/index.pdf.
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The present study considers the numerical simulation of the different flow characteristics involved in the conjugate heat transfer analysis of an internally cooled gas turbine blade. Conjugate simulations require full coupling of convective heat transfer in fluid regions to the heat diffusion in solid regions. Therefore, accurate prediction of heat transfer quantities on both external and internal surfaces has the uppermost importance and highly connected with the performance of the employed turbulence models. The complex flow on both surfaces of the internally cooled turbine blades is caused from the boundary layer laminar-to-turbulence transition, shock wave interaction with boundary layer, high streamline curvature and sequential flow separation. In order to discover the performances of different turbulence models on these flow types, analyses have been conducted on five different experimental studies each concerned with different flow and heat transfer characteristics. Each experimental study has been examined with four different turbulence models available in the commercial software (ANSYS FLUENT13.0) to decide most suitable RANS-based turbulence model. The Realizable k-&epsilonmodel, Shear Stress Transport k-&omega
model, Reynolds Stress Model and V2-f model, which became increasingly popular during the last few years, have been used at the numerical simulations. According to conducted analyses, despite a few unreasonable predictions, in the majority of the numerical simulations, V2-f model outperforms other first-order turbulence models (Realizable k-&epsilon
and Shear Stress Transport k-&omega
) in terms of accuracy and Reynolds Stress Model in terms of convergence.
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Boiani, Davide. "Finite element structural and thermal analysis of JT9D turbofan engine first stage turbine blade." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/12566/.
Full textAbstract:
The objective of this work was to conduct a preliminary finite element static structural and transient thermal analyses of a first stage turbine blade which was previously assembled on a Pratt & Whitney JT9D-7A turbofan engine. This turbine blade was obtained from a collector of aircraft scrap parts. After an extensive theoretical background on airbreathing jet engines and materials used for such components, the process behind the creation of a 3D model was explained. The laser scanning technique and a piezoeletric digitizer were employed to recreate the blade inside a 3D modelling software. The model was then imported into the finite element analysis software ANSYS; the analyses were performed, and the most interesting results were evaluated. The structural and thermal results were found to be congruous with the literature on similar applications of components with the same material, and appear to be a realistic representation of the blade behaviour inside the first stage turbine environment.
Books on the topic "Aeronautical turbine"
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Rogo, C. Variable area radial turbine fabrication and test program. [Cleveland, Ohio: Army Aviation Research & Technology Activity, Propulsion Directorate, 1986.
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Bill, Gunston. The development of jet and turbine aero engines. Yeovil: Patrick Stephens, 1995.
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Center), NASA-Chinese Aeronautical Establishment (CAE) Symposium (1985 NASA Lewis Research. Combustion fundamentals: NASA-Chinese Aeronautical Establishment (CAE) Symposium. [Washington, DC]: National Aeronautics and Space Administration, Scientific and Technical Information Branch, 1987.
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Aerothermodynamics of gas turbine and rocket propulsion. 3rd ed. Reston, VA: American Institute of Aeronautics and Astronautics, 1997.
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Aerothermodynamics of gas turbine and rocket propulsion. Washington, DC: American Institute of Aeronautics and Astronautics, 1988.
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L, Braslow Albert, Butterfield A. J, and Langley Research Center, eds. Circulation control propellers for general aviation, including a BASIC computer program. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1985.
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1959-, Pierre Christophe, and United States. National Aeronautics and Space Administration., eds. Stochastic sensitivity measure for mistuned high-performance turbines. [Washington, DC]: National Aeronautics and Space Administration, 1992.
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J, Holt Mark, ed. The turbine pilot's flight manual. Ames: Iowa State University Press, 1995.
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J, Holt Mark, ed. The turbine pilot's flight manual. 2nd ed. Ames: Iowa State University Press, 2001.
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C, Smith Steven. Airflow calibration of a bellmouth inlet for measurement of compressor airflow in turbine-powered propulsion simulators. Moffett Field, Calif: National Aeronautics and Space Administration, Ames Research Center, 1985.
Find full textBook chapters on the topic "Aeronautical turbine"
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Xu, You Liang, Cheng Li Liu, and Zhen Zhou Lu. "Fuzzy-Random FOSM and its Application in Low Cycle Fatigue Life Reliability Analysis of an Aeronautical Engine Turbine Disk." In Fracture and Damage Mechanics V, 775–78. Stafa: Trans Tech Publications Ltd., 2006. http://dx.doi.org/10.4028/0-87849-413-8.775.
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Vinogradov, K., and G. Kretinin. "Application of UQ for Turbine Blade CHT Computations." In Uncertainty Management for Robust Industrial Design in Aeronautics, 365–81. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-77767-2_23.
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"Engine MDO Deployed on a Two-Stage Turbine." In Advances in Collaborative Civil Aeronautical Multidisciplinary Design Optimization, 289–330. Reston ,VA: American Institute of Aeronautics and Astronautics, 2010. http://dx.doi.org/10.2514/5.9781600867279.0289.0330.
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Azevedo, Jéssica Fernanda de, Viviane Teleginski Mazur, Daniele Cristina Chagas, Júlio César Gomes Santos, Maurício Marlon Mazur, and Getúlio de Vasconcelos. "THICKNESS CONTROL OF COATINGS DEPOSITED BY CO2 LASER FOR AERONAUTICAL TURBINE BLADES." In Engenharia Mecânica: Inovações Tecnológicas de Elevado Valor, 1–7. Atena Editora, 2021. http://dx.doi.org/10.22533/at.ed.8262109021.
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Tudosie, Alexandru-Nicolae. "Aircraft Gas-Turbine Engine’s Control Based on the Fuel Injection Control." In Aeronautics and Astronautics. InTech, 2011. http://dx.doi.org/10.5772/17986.
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Kollmann, Karl, Calum E. Douglas, and S. Can Gülen. "Prelude." In Turbo/Supercharger Compressors and Turbines for Aircraft Propulsion in WWII: Theory, History and Practice—Guidance from the Past for Modern Engineers and Students, 1–7. ASME, 2021. http://dx.doi.org/10.1115/1.884676_ch1.
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Prof. Dr.-Ing. Kollmann is one of the most important aeronautical engineers in the story of piston aeroengine development in Germany in WWII. In 12 years, Dr.-Ing. Kollmann progressed from the role of senior engineer to chief engineer of the aeroengine design department in Daimler-Benz. This book is an historical record of his own engineering work in developing high performance piston aeroengines. The original document that Dr.-Ing. Kollmann wrote in 1947 is presented here in English with extensive additional material by the authors.
Conference papers on the topic "Aeronautical turbine"
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Rouser, Kurt P., Caitlin R. Thorn, Aaron R. Byerley, Charles F. Wisniewski, Scott R. Nowlin, and Kenneth W. Van Treuren. "Integration of a Turbine Cascade Facility Into an Undergraduate Thermo-Propulsion Sequence." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-94744.
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The Department of Aeronautics at the United States Air Force Academy utilizes a closed-loop, two-dimensional turbine cascade wind tunnel to reinforce a learning-focused undergraduate thermo-propulsion sequence. While previous work presented in the literature outlined the Academy thermo-propulsion sequence and the contextual framework for instruction, this current paper addresses how the Academy turbine cascade facility is integrated into the aeronautical engineering course sequence. Cadets who concentrate in propulsion are to some extent prepared for each successive course through their contact with the cascade, and ultimately they graduate with an exposure to experimental research that enhances their grasp of gas turbine engine fundamentals. Initially, the cascade is used to reinforce airfoil theory to all cadets in the Fundamentals of Aeronautics course. Aeronautical engineering majors take this course during the first semester of their sophomore year. The next semester all aeronautical engineering majors take Introduction to Aero-thermodynamics. In this course, the closed-loop aspect of the cascade facility is used to reinforce concepts of work addition to the flow. Heat transfer is also discussed, using the heat exchanger that regulates test section temperature. Exposure to the cascade also prepares cadets for the ensuing Introduction to Propulsion and Aeronautics Laboratory courses, taken in the junior and senior year, respectively. In the propulsion course, cadets connect thermodynamic principles to component analysis. In the laboratory course, cadets work in pairs on propulsion projects sponsored by the Air Force Research Laboratory, including projects in the cascade wind tunnel. Individual cadets are selected from the cascade research teams for summer internships, working at an Air Force Research Laboratory turbine cascade tunnel. Ultimately, cadet experiences with the Academy turbine cascade help lay the foundation for a two-part senior propulsion capstone sequence in which cadets design a gas turbine engine starting with the overall cycle selection leading to component-level design. The turbine cascade also serves to integrate propulsion principles and fluid mechanics through a senior elective Computational Fluid Dynamics course. In this course, cadets may select a computational project related to the cascade. Cadets who complete the thermo-propulsion sequence graduate with a thorough understanding of turbine engine fundamentals from both conceptual and applied perspectives. Their exposure to the cascade facility is an important part of the process. An assessment of cadet learning is presented to validate the effectiveness of this integrated research-classroom approach.
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Tomita, Jesuino Takachi, João Roberto Barbosa, and Cleverson Bringhenti. "The Flow Machines Course at the Technological Institute of Aeronautics for Mechanical-Aeronautical Engineering Undergraduate Course." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-95228.
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Undergraduate courses at Technological Institute of Aeronautics (ITA) are 5-years course, divided into Fundamental (2 years) and Professional (3 years). The Flow Machines, in the Mechanical-Aeronautical Engineering Course, is offered by the Turbomachines Department and is taught in the first semester of the fourth year (2nd professional year). In the course, the basic theory, unified for all machines, is presented in details for the students, emphasizing the physics of all processes involved in the fluid-machine energy transfer. Incompressible and compressible fluids are treated accordingly. The flow machines types are individually studied, focusing attention to their performance characteristics and range of applications. The preliminary design and off-design operation issues are discussed in details with the students, with emphasis on relevant aspects of each machine, like cavitation, stall and surge. The students are taught on how to choose the flow properties at the blade edges for the sake of preliminary design and off-design performance estimations. Loss models are introduced during the theory classes and popular models are presented. At this point, in-house computer codes and commercial software are presented to the students, who are asked to solve simple problems. The installation, operation and basic performance calculations are also presented for the students during the lab classes for several hydraulic machines installed at ITA laboratories. All course material is transferred for the students in pdf format before classes. In this work, the experience with the teaching process in flow machines at ITA, theory and laboratory, is described.
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Silva, Elizabete, and Reyolando Brasil. "Localization of vibration modes in aeronautical turbine blades." In 8th International Symposium on Solid Mechanics. ABCM, 2022. http://dx.doi.org/10.26678/abcm.mecsol2022.msl22-0129.
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Andriani, Roberto, Fausto Gamma, and Umberto Ghezzi. "Main Effects of Intercooling and Regeneration on Aeronautical Gas Turbine Engines." In 46th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2010. http://dx.doi.org/10.2514/6.2010-6539.
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Cirtwill, Joseph D., Sina Kheirkhah, Pankaj Saini, Krishna Venkatesan, and Adam M. Steinberg. "Analysis of intermittent thermoacoustic oscillations in an aeronautical gas turbine combustor." In 55th AIAA Aerospace Sciences Meeting. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2017. http://dx.doi.org/10.2514/6.2017-0824.
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Motheau, Emmanuel, Franck Nicoud, Yoann Mery, and Thierry Poinsot. "Analysis and Modelling of Entropy Modes in a Realistic Aeronautical Gas Turbine." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-94224.
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A combustion instability in a combustor typical of aero-engines is analyzed and modeled thanks to a low order Helmholtz solver. A Dynamic Mode Decomposition (DMD) is first applied to the Large Eddy Simulation (LES) database. The mode with the highest amplitude shares the same frequency of oscillation as the experiment (approx. 350 Hz) and it shows the presence of large entropy spots generated within the combustion chamber and convected down to the exit nozzle. The lowest purely acoustic mode being in the range 650–700 Hz, it is postulated that the instability observed around 350 Hz stems from a mixed entropy/acoustic mode where the acoustic generation associated with the entropy spots being convected throughout the choked nozzle plays a key role. A Delayed Entropy Coupled Boundary Condition is then derived in order to account for this interaction in the framework of a Helmholtz solver where the baseline flow is assumed at rest. When fed with appropriate transfer functions to model the entropy generation and convection from the flame to the exit, the Helmholtz solver proves able to predict the presence of an unstable mode around 350 Hz, in agreement with both the LES and the experiments. This finding supports the idea that the instability observed in the combustor is indeed driven by the entropy/acoustic coupling.
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Ma, Zhiwen, Comas Haynes, and Pinakin Patel. "System Level Synthesis, Modeling and Roadmapping for Aeronautical SOFC/Gas Turbine Hybrid Systems." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-80055.
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Solid oxide fuel cell /gas turbine (SOFC/GT) hybrid power systems have been recognized as having the potential to operate at unprecedented levels of performance (e.g., 50%+ electrical power generation efficiencies with significantly mitigated greenhouse gas, criteria pollutant and noise emissions). Although the emphasis has been upon land applications, there are aeronautical benefits that may be derived as well. Despite these benefits, there have been limited investigations into the technical merit and feasibility of incorporating these hybrid systems onboard aerovehicles. A feasibility investigation has been performed in conjunction with fuel cell system modeling capabilities to conceptually establish auxiliary power system possibilities as well as the viability technology gaps.
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Rolling, August J., Aaron R. Byerley, and Charles F. Wisniewski. "Integrating Systems Engineering Into the USAF Academy Capstone Gas Turbine Engine Course." In ASME 2011 Turbo Expo: Turbine Technical Conference and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/gt2011-46440.
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This paper is intended to serve as a template for incorporating technical management majors into a traditional engineering design course. In 2002, the Secretary of the Air Force encouraged the USAF Academy to initiate a new interdisciplinary academic major related to systems engineering. This direction was given in an effort to help meet the Air Force’s growing need for “systems” minded officers to manage the development and acquisition of its ever more complex weapons systems. The curriculum for the new systems engineering management (SEM) major is related to the “engineering of large, complex systems and the integration of the many subsystems that comprise the larger system” and differs in the level of technical content from the traditional engineering major. The program allows emphasis in specific cadet-selected engineering tracks with additional course work in human systems, operations research, and program management. Specifically, this paper documents how individual SEM majors have been integrated into aeronautical engineering design teams within a senior level capstone course to complete the preliminary design of a gas turbine engine. As the Aeronautical engineering (AE) cadets performed the detailed engine design, the SEM cadets were responsible for tracking performance, cost, schedule, and technical risk. Internal and external student assessments indicate that this integration has been successful at exposing both the AE majors and the SEM majors to the benefits of “systems thinking” by giving all the opportunity to employ SE tools in the context of a realistic aircraft engine design project.
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Giusti, Andrea, Luca Magri, and Marco Zedda. "Flow Inhomogeneities in a Realistic Aeronautical Gas-Turbine Combustor: Formation, Evolution and Indirect Noise." In ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/gt2018-76436.
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Indirect noise generated by the acceleration of combustion inhomogeneities is an important aspect in the design of aeroengines because of its impact on the overall noise emitted by an aircraft and the possible contribution to combustion instabilities. In this study, a realistic rich-quench-lean combustor is numerically investigated, with the objective of quantitatively analyzing the formation and evolution of flow inhomogeneities and determine the level of indirect combustion noise in the nozzle guide vane (NGV). Both entropy and compositional noise are calculated in this work. A high-fidelity numerical simulation of the combustion chamber, based on the Large-Eddy Simulation (LES) approach with the Conditional Moment Closure (CMC) combustion model, is performed. The contributions of the different air streams to the formation of flow inhomogeneities are pinned down and separated with seven dedicated passive scalars. LES-CMC results are then used to determine the acoustic sources to feed an NGV aeroacoustic model, which outputs the noise generated by entropy and compositional inhomogeneities. Results show that non-negligible fluctuations of temperature and composition reach the combustor’s exit. Combustion inhomogeneities originate both from finite-rate chemistry effects and incomplete mixing. In particular, the role of mixing with dilution and liner air flows on the level of combustion inhomogeneities at the combustor’s exit is highlighted. The species that most contribute to indirect noise are identified and the transfer functions of a realistic NGV are computed. The noise level indicates that indirect noise generated by temperature fluctuations is larger that the indirect noise generated by compositional inhomogeneities, although the latter is not negligible and is expected to become louder in supersonic nozzles. It is also shown that relatively small fluctuations of the local flame structure can lead to significant variations of the nozzle transfer function, whose gain increases with the Mach number. This highlights the necessity of an on-line solution of the local flame structure, which is performed in this paper by CMC, for an accurate prediction of the level of compositional noise. This study opens new possibilities for the identification, separation and calculation of the sources of indirect combustion noise in realistic aeronautical gas turbines.
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Byerley, Aaron R., August J. Rolling, and Kenneth W. Van Treuren. "Estimating Gas Turbine Engine Weight, Costs, and Development Time During the Preliminary Aircraft Engine Design Process." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-95778.
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This paper describes the application of a weight and cost-estimating methodology used in an undergraduate aircraft engine design course that is taught in concert with a companion course in airframe design. The two preliminary designs, one for the engine and the other for the airframe, must be integrated as subsystems within a system to satisfy the performance requirements of a given mission as outlined in a single “request for proposals”. In recent years, systems engineering management majors have been added to the design teams to work alongside the aeronautical engineering majors to analyze and report on costs, schedule, and technical risk factors in addition to the operational performance factors that have previously been the sole focus of the course. The teaming of technical management majors and aeronautical engineering majors has been driven by a heightened emphasis on system affordability. The cost-estimating methodology for gas turbine engines uses cycle parameters such as turbine rotor inlet temperature, overall pressure ratio, specific fuel consumption, level of technology, and engine dry weight as inputs. A methodology for estimating dry engine weight was developed which uses engine cycle parameters and fan face diameter as inputs in a volume analog scaling factor which was correlated against historical engine weight data. To tie all of the performance, weight, cost, and development time issues together, the paper presents an “analysis of alternatives” example that considers three different engine cycle alternatives. The design tools presented in this paper will provide a strong foundational understanding of how to systematically weigh and evaluate the important tradeoffs between aircraft turbofan engine performance, cost, schedule, and risk factors. Equipping students with the insight and ability to perform these multidisciplinary trade studies during the preliminary engine design process is this paper’s most important contribution.