Journal articles: '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.

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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 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.

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Radkowski, Grzegorz, and Jaroslaw Sep. "Surface Quality of Amilled Gamma Titaniumaluminide for Aeronautical Applications." Management and Production Engineering Review 5, no. 2 (June 1, 2014): 60–65. http://dx.doi.org/10.2478/mper-2014-0018.

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Abstract Gamma titanium aluminides are an interesting alternative for nickel, iron or cobalt matrix superalloys. Due to the advantageous strength properties at high temperatures they can successfully replace superalloys in applications such as high pressure compressor blades, low pressure turbine blades, high pressure compressor case, low pressure turbine case. Milling is one of the processes that can be applied in the forming elements made from this type of alloys for the aviation industry. Research included the selection of tool, the process kinematics and the range of milling gamma titanium aluminide (Ti-45Al-5Nb-0.2B-0.2C) process parameters were carried out. Milling can be an effective method of forming of elements made of gamma TiAL in the range of processing parameters: vc = 20-70 m/min, ap = 0.3-0.7 mm, fz = 0.1- 0.45 mm/tooth. In the tests carried out the best results were obtained using a R300-016A20L- 08L milling cutter, S30T tool coating and in-cut milling.

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Amato, Giorgio, Matteo Giovannini, Michele Marconcini, and Andrea Arnone. "Unsteady Methods Applied to a Transonic Aeronautical Gas Turbine Stage." Energy Procedia 148 (August 2018): 74–81. http://dx.doi.org/10.1016/j.egypro.2018.08.032.

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Dzięgielewski, Wojciech, Bartosz Gawron, and Andrzej Kulczycki. "Low Temperature Properties Of Fuel Mixtures Of Kerosene And Fame Type Used To Supply Turbine Engines In Marine And Other Non-Aeronautical Applications." Polish Maritime Research 22, no. 2 (April 1, 2015): 101–5. http://dx.doi.org/10.1515/pomr-2015-0023.

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Abstract A worldwide trend to popularise gradually increasing use of biofuels in various applications was a motivation for gaining interest in FAME as a commonly available biocomponent to fuels combusted in turbine engines. These engines are mainly used in aeronautics, but many of them are also used in other, non-aeronautical areas, including marine navigation. Specific conditions in which fuels are combusted in turbine engines used in these applications are the reason why fuel mixtures of kerosene and FAME type should reveal relevant low temperature characteristics. The article presents results of tests of low temperature properties of mixtures of the jet fuel Jet A-1 and methyl esters of higher fatty acids (FAME). The prepared mixtures contained different contents of FAME. The obtained results present changes of: viscosity, cloud point, pour point, crystallising point, and cold filter plugging point, depending on the percentage by volume of FAME. They also prove that the course of changes of low temperature properties of these mixtures is affected by chemical structure of the biocomponent.

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Beranoagirre, A., and Luis Norberto López de Lacalle. "Topography Prediction on Grinding of Emerging Aeronautical TiAl Intermetallic Alloys." Materials Science Forum 797 (June 2014): 84–89. http://dx.doi.org/10.4028/www.scientific.net/msf.797.84.

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Gamma-TiAl intermetallic materials are the focus of all leading aerospace / gas turbine manufacturers, as a replacement for some nickel-based superalloy components in parts of the engine subject to temperatures < 900°C. Although applicable for only a relatively narrow range of applications, titanium intermetallic materials are likely to play a significant role in the production of future aeroengines. This work presents the results from grinding tests on two types of Gamma TiAl alloys.

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Fernandez-Gamiz, Unai, Iñigo Errasti, Ekaitz Zulueta, José Manuel Lopez Guede, and Ana Boyano. "Computational characterization of a Gurney flap on a DU91(2)W250 airfoil." MATEC Web of Conferences 307 (2020): 01053. http://dx.doi.org/10.1051/matecconf/202030701053.

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The considerable increase of wind turbine rotor size and weight in the last years has made impossible to control as they were controlled 20 years ago. The cost of energy is an essential role to maintain this type of energy as a viable alternative in economic terms with traditional or other renewable energies. Through the last decades many different flow control devices have been developed. Most of them were shaped for aeronautical issues and this was its first research application. Currently researchers are working to optimize and introduce these types of devices in multi megawatt wind turbines. Gurney flap (GF) is a vane perpendicular to the airfoil surface with a size between 0.1 and 3% of the airfoil chord length, placed in the lower or upper side of the airfoil close to the trailing edge of the airfoil. When GFs are appropriately designed, they increase the total lift of the airfoil while reducing the drag. Thanks to the implementation of the of this flow control device the efficiency of a wind turbine improves, which results on an increase in the power generation.

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Sarnecki, Jarosław, Tomasz Białecki, Bartosz Gawron, Jadwiga Głąb, Jarosław Kamiński, Andrzej Kulczycki, and Katarzyna Romanyk. "Thermal Degradation Process of Semi-Synthetic Fuels for Gas Turbine Engines in Non-Aeronautical Applications." Polish Maritime Research 26, no. 1 (March 1, 2019): 65–71. http://dx.doi.org/10.2478/pomr-2019-0008.

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Abstract This article concerns the issue of thermal degradation process of fuels, important from the perspective of the operation of turbine engines, especially in the context of new fuels/bio-fuels and their implementation. The studies of the kerosene-based jet fuel (Jet A-1) and its blends with synthetic components manufactured according to HEFA and ATJ technology, were presented. Both technologies are currently approved by ASTM D7566 to produce components to be added to turbine fuels. Test rig investigations were carried out according to specific methodology which reflects the phenomena taking place in fuel systems of turbine engines. The mechanism of thermal degradation process was assessed on the basis of test results for selected properties, IR spectroscopy and calculation of activation energy. The results show that with the increase of the applied temperature there is an increment of the content of solid contaminants, water and acid for all tested fuels. Thermal degradation process is different for conventional jet fuel when compared to blends, but also semi-synthetic fuels distinguished by different thermal stability depending on a given manufacturing technology.

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Fąfara, Jean-Marc. "Overview of low emission combustors of aircraft turbine drive units." Combustion Engines 183, no. 4 (December 15, 2020): 45–49. http://dx.doi.org/10.19206/ce-2020-407.

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It is important to notice that aircraft turbine drive units are commonly used in the modern aviation. The piston engines are often reserved for small and/or sportive aircraft. The turbine drive units are also combustion engine. This paper presents the most popular combustors used in the aeronautical turbine engines. Firstly there are listed the requirements that a combustor has to achieve. Then are presented the combustor designs that permit to achieve the firstly presented requirements. In this work are presented the LPP, TAPS, RQL, graduated combustion zone, VGC, exhaust recirculation system combustors. For each combustor design is enlighten its principle of work, described the etymology of the given name to this design and shown a scheme. The work is closed by a briefly conclusion about the described combustor.

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Schafrik, Robert, and Robert Sprague. "Superalloy Technology - A Perspective on Critical Innovations for Turbine Engines." Key Engineering Materials 380 (March 2008): 113–34. http://dx.doi.org/10.4028/www.scientific.net/kem.380.113.

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High temperature structural materials, such as nickel-based superalloys, have contributed immensely to societal benefit. These materials provide the backbone for many applications within key industries that include chemical and metallurgical processing, oil and gas extraction and refining, energy generation, and aerospace propulsion. Within this broad application space, the best known challenges tackled by these materials have arisen from the demand for large, efficient land-based power turbines and light-weight, highly durable aeronautical jet engines. So impressive has the success of these materials been that some have described the last half of the 20th century as the Superalloy Age. Many challenges, technical and otherwise, were overcome to achieve successful applications. This paper highlights some of the key developments in nickel superalloy technology, principally from the perspective of aeronautical applications. In the past, it was not unusual for development programs to stretch out 10 to 20 years as the materials technology was developed, followed by the development of engineering practice, and lengthy production scaleup. And many developments fell by the wayside. Today, there continue to be many demands for improved high temperature materials. New classes of materials, such as intermetallics and ceramic materials, are challenging superalloys for key applications, given the conventional wisdom that superalloys are reaching their natural entitlement level. Therefore, multiple driving forces are converging that motivate improvements in the superalloy development process. This paper concludes with a description of a new development paradigm that emphasizes creativity, development speed, and customer value that can provide superalloys that meet new needs.

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Akkus, Mahmut Burak, Zeki Haksever, and Suleyman Teksin. "Experimental and Numerical Analysis of Savonius Wind Turbine with End Plate on Various Types." Energy, Environment and Storage 2, no. 2 (May 17, 2022): 54–63. http://dx.doi.org/10.52924/iujx7477.

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This study aims to observe whether the overall yield has changed utilizing the different blade structures and the end plates placed on the different blade structures of the Savonius-type wind turbine. End plates of different diameters are placed at the top and bottom of the turbine to increase overall efficiency.While the experimental analysis was conducted in the aerodynamic laboratory of the faculty of Aeronautical and Astronauticalat Erciyes University, Ansys Fluent software is used for numerical calculations.The turbine structure used for the numerical study is made according to the optimum values taken from the experimental investigationto minimize the time wasted. The results in the experimental and numerical analysis were compared with each other and the overall yield was observed to increase according to these analysis results. The presence of the end plate significantly increased the efficiency of the savonius turbine and allowed it to operate in the higher TSR range.This increase is directly proportional to the enlarging in the diameter of the end plate

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Liu, Han Wu, Nan Li, Qiao Nan Tian, and De Chao Dong. "Microstructure Changes and Computer Simulation of K4169 Superalloy Using Chemical Grain Refinement Casting." Advanced Materials Research 189-193 (February 2011): 3954–59. http://dx.doi.org/10.4028/www.scientific.net/amr.189-193.3954.

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As an important aeronautical assembly materials, such as aeronautical gas turbine and turbine plate et al, K4169 alloy has enough high ability of resistance to high temperature deformation and a long low-period fatigue life when working, and its grain structure should be equiaxed dendrite as fine as possible in casting. Chemical grain refinement method was used to refine K4169 alloy to satisfy the demands mentioned above. By using new intermetallic compound grain refiners, chemical grain refinement casting technology was carried out to refine K4169 superalloy. The results show that the grain morphology has been transformed from dendrite to granulation, the average principal axis length of the primary dendrites has been shorted and the segregation ratios of main alloy elements mitigate with the decrease of grain size in fine-grained castings, which indicates the remarkable effects of grain refinement. In addition, basing on the model of equiaxed dendrite growth solute diffusion, continuous nucleation model, dendrite tip growth kinetics model and cellular automata (CA) technique to coupled simulate the grain structure formation process of K4169 alloy in chemical grain refinement casting, which agreed very well with experiments results, this will do much contribution to the theoretic base for studying high temperature mechanics performance and performance of resistance to corrosion of K4169 superalloy.

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Férand, Mélissa, Thomas Livebardon, Stéphane Moreau, and Marlène Sanjosé. "Numerical Prediction of Far-Field Combustion Noise from Aeronautical Engines." Acoustics 1, no. 1 (February 19, 2019): 174–98. http://dx.doi.org/10.3390/acoustics1010012.

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A hybrid methodology combining a detailed Large Eddy Simulation of a combustion chamber sector, an analytical propagation model of the extracted acoustic and entropy waves at the combustor exit through the turbine stages, and a far-field acoustic propagation through a variable exhaust temperature field was shown to predict far-field combustion noise from helicopter and aircraft propulsion systems accurately for the first time. For the single-stream turboshaft engine, the validation was achieved from engine core to the turbine exit. Propagation to the far field was then performed through a modeled axisymmetric jet. Its temperature modified the acoustic propagation of combustion noise significantly and a simple analytical model based on the Snell–Descarte law was shown to predict the directivity for axisymmetric single jet exhaust accurately. Good agreement with measured far-field spectra for all turboshaft-engine regimes below 2 kHz stresses that combustion noise is most likely the dominant noise source at low frequencies in such engines. For the more complex dual-stream turbofan engine, two regime computations showed that direct noise is mostly generated by the unsteady flame dynamics and the indirect combustion noise by the temperature stratification induced by the dilution holes in the combustion chamber, as found previously in the turboshaft case. However, in the turboengine, direct noise was found dominant at the combustor exit for the low power case and equivalent contributions of both combustion noise sources for the high power case. The propagation to the far-field was achieved through the temperature field provided by a Reynolds-Averaged Navier–Stokes simulation. Good agreement with measured spectra was also found at low frequencies for the low power turboengine case. At high power, however, turboengine jet noise overcomes combustion noise at low frequencies.

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Boudier, G., L. Y. M. Gicquel, T. Poinsot, D. Bissières, and C. Bérat. "Comparison of LES, RANS and experiments in an aeronautical gas turbine combustion chamber." Proceedings of the Combustion Institute 31, no. 2 (January 2007): 3075–82. http://dx.doi.org/10.1016/j.proci.2006.07.067.

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Torres-Carrillo, Sharon, Héctor R. Siller, Carlos Vila, Cecilio López, and Ciro A. Rodríguez. "Environmental analysis of selective laser melting in the manufacturing of aeronautical turbine blades." Journal of Cleaner Production 246 (February 2020): 119068. http://dx.doi.org/10.1016/j.jclepro.2019.119068.

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Deodati, Paolo, Riccardo Donnini, Saulius Kaciulis, Majid Kazemian-Abyaneh, Alessio Mezzi, Roberto Montanari, Claudio Testani, and Nadia Ucciardello. "Micro-Chemistry and Mechanical Behaviour of Ti6Al4V-SiC_f Composite Produced by HIP for Aeronautical Applications." Materials Science Forum 678 (February 2011): 23–47. http://dx.doi.org/10.4028/www.scientific.net/msf.678.23.

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The paper reports the results of an extensive characterization of the Ti6Al4V-SiCfcomposite produced by hot isostatic pressing (HIP) to assess its capability to withstand the in-service conditions of turbine blades operating at middle temperatures in aeronautical engines. The microstructure of composite, in as-fabricated condition and after long-term heat treatments (up to 1,000 hours) in the temperature range 673-873 K, has been investigated by means of different techniques. Particular attention was paid to the micro-chemical evolution of fibre-matrix interface which is scarcely affected also by the most severe heat treatments examined here. This leads to stable mechanical properties as evidenced by hardness, tensile and FIMEC instrumented indentation tests. Therefore, the composite can operate at the maximum temperature (873 K) foreseen for its aeronautical applications without remarkable modifications of its microstructure and degradation of mechanical properties. The mechanical characterization has been completed by internal friction and dynamic modulus measurements carried out both at constant and increasing temperature, from 80 to 1173 K.

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Pinelli, Lorenzo, Michele Marconcini, Roberto Pacciani, Friedrich Bake, Karsten Knobloch, Paolo Gaetani, and Giacomo Persico. "Effect of clocking on entropy noise generation within an aeronautical high pressure turbine stage." Journal of Sound and Vibration 529 (July 2022): 116900. http://dx.doi.org/10.1016/j.jsv.2022.116900.

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Masson, Christian, Idriss Ammara, and Ion Paraschivoiu. "An Aerodynamic Method for the Analysis of Isolated Horizontal-Axis Wind Turbines." International Journal of Rotating Machinery 3, no. 1 (1997): 21–32. http://dx.doi.org/10.1155/s1023621x97000031.

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The aerodynamic analysis of a wind turbine represents a very complex task since it involves an unsteady three-dimensional viscous flow. In most existing performance-analysis methods, wind turbines are considered isolated so that interference effects caused by other rotors or by the site topology are neglected. Studying these effects in order to optimize the arrangement and the positioning of Horizontal-Axis Wind Turbines (HAWTs) on a wind farm is one of the research activities of the Bombardier Aeronautical Chair. As a preliminary step in the progress of this project, a method that includes some of the essential ingredients for the analysis of wind farms has been developed and is presented in the paper. In this proposed method, the flow field around isolated HAWTs is predicted by solving the steady-state, incompressible, two-dimensional axisymmetric Navier-Stokes equations. The turbine is represented by a distribution of momentum sources. The resulting governing equations are solved using a Control-Volume Finite Element Method (CVFEM). This axisymmetric implementation efficiently illustrates the applicability and viability of the proposed methodology, by using a formulation that necessitates a minimum of computer resources. The axisymmetric method produces performance predictions for isolated machines with the same level of accuracy than the well-known momentum-strip theory. It can therefore be considered to be a useful tool for the design of HAWTs. Its main advantage, however, is its capacity to predict the flow in the wake which constitutes one of the essential features needed for the performance predictions of wind farms of dense cluster arrangements.

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Hu, Ke-Qi, Yi-Fan Xia, Yao Zheng, and Gao-Feng Wang. "Effects of inlet turbulence intensity on wall heat transfer in a turbine guide vane." International Journal of Modern Physics B 34, no. 14n16 (May 30, 2020): 2040082. http://dx.doi.org/10.1142/s0217979220400822.

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Heat transfer is an important phenomenon that exists in many industrial applications, especially for gas turbines, aeronautical engines. In this work, two different turbulence models ([Formula: see text] and SAS model) are used to investigate the effects of inlet turbulence on wall heat transfer and the characteristics of flow field in a well-known turbine guide vane (LS89). In order to handle the transition, Menter’s [Formula: see text] transition model is used. The simulations show that the inlet turbulence has an apparent effect on the wall heat transfer of the vane. Not only the maximum wall heat transfer coefficient is increased, the distribution of wall heat flux at the suction side is also modified. The isentropic Mach number along the vane surface is insensitive to the variance of inlet turbulence intensity. Besides, a shock appears in the throat and a laminar-to-turbulence transition position moves forward after the main flow turbulence is enhanced. Moreover, the results indicate that SAS model is capable of capturing more flow structures such as reflecting pressure waves and shedding vortexes while the [Formula: see text] model misses them due to the dissipation.

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Santin, M., A. Traverso, and A. Massardo. "Technological aspects of gas turbine and fuel cell hybrid systems for aircraft: a review." Aeronautical Journal 112, no. 1134 (August 2008): 459–67. http://dx.doi.org/10.1017/s0001924000002426.

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The objective of this work is to make an overview of opportunities and issues related to the aeronautical application of solid oxide fuel cell hybrid systems. The great interest on fuel cells comes from their capacity of producing electric energy with high efficiency at low pollutant production. The application of these systems as full-time auxiliary power units is an interesting alternative in a future scenario, which is supposed to include a More Electric Aircraft and more restrictive environmental standards. A review of the technological aspects of this application is presented. The physical models found in literature were investigated and the results were compared and discussed.

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Xu, Qing Yan, Bin Li, and Bai Cheng Liu. "Application of Microstructure Simulation by Modified CA Method to Al Alloy Casting Production." Materials Science Forum 618-619 (April 2009): 199–202. http://dx.doi.org/10.4028/www.scientific.net/msf.618-619.199.

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Aluminum casting is widely used in aeronautical, automobile and other industries nowadays. The Cellular Automaton (CA) method was modified to simulate the microstructure evolution of Al alloy casting. Simulated program code was developed and applied into Al casting production. A nucleation model was investigated based upon the experimental data. The solute diffusion in the liquid and solid phases was also considered in developing a grain growth model. With the developed models, not only grain structure but also dendritic microstructure can be predicted during the solidification process. The microstructure simulation of the Al alloy turbine wheel was studied in detail.

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30

Silva, José M., Ricardo A. Cláudio, A. Sousa e Brito, Carlos M. Branco, and Jim Byrne. "Characterization of Powder Metallurgy (PM) Nickel Base Superalloys for Aeronautical Applications." Materials Science Forum 514-516 (May 2006): 495–99. http://dx.doi.org/10.4028/www.scientific.net/msf.514-516.495.

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During the last decade, some major improvements have been achieved concerning the evaluation of new types of materials suitable for aeronautical components exposed to severe operational conditions, such as turbine disks. Due to their outstanding mechanical properties, nickel base superalloys assumed a preferential position when compared with other conventional metallic alloys, benefiting from both their superior fatigue strength and high temperature behaviour. However, these alloys evince a high sensibility concerning possible defects that can arise due to certain types of loading, such as porosities and cavities associated with creep-fatigue at high temperatures. The present paper compiles some experimental results obtained for two types of recent nickel base superalloys. Some fatigue tests were performed using two configurations of these materials: a set of Udimet 720Li specimens (CT geometry) and a set of RR1000 specimens (CN geometry). A maximum temperature of 650°C was considered in both types of materials. The mechanical properties of these alloys were inferred via typical FCGR parameters, such as da/dN vs K curves, complemented with detailed analyses of the cracking mechanisms based on SEM observations. Finally, some metallographic characterization tests were carried out in order to determine the average grain size of these PM alloys and to confirm the presence of important microstructural constituents that can influence the overall fatigue performance of these materials.

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31

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." Key Engineering Materials 324-325 (November 2006): 775–78. http://dx.doi.org/10.4028/www.scientific.net/kem.324-325.775.

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An approximate analytical method is presented to analyze reliability for the structure with fuzzy-random uncertainty in basic variables. On the basis of equivalent transformation from fuzzy possibility distribution (FPD) to random probability distribution (RPD), this contribution expands first order and second moment method (FOSM) for random reliability to that for fuzzy-random reliability. The expanded FOSM is illustrated by the way of the fuzzy-random low fatigue life reliability analysis about an aeronautical engine disk affected by fuzzy-random uncertainty. Comparison between the FOSM and the numerical simulation for the fuzzy-random reliability demonstrates the precision of the presented computational model.

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32

Zhang, Dong Jin, Chen Wang, Gang Liu, and Ming Chen. "A FEM and Experiment Study on High Speed Machining of Nickel-Based Superalloy GH4169." Key Engineering Materials 375-376 (March 2008): 82–86. http://dx.doi.org/10.4028/www.scientific.net/kem.375-376.82.

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As a typical difficult-to-cut material, the nickel-based superalloy GH4169 has been used in many kinds of aeronautical key structures and turbine components because of its high yield stress and anti-fatigue performance even in high temperature. In this paper, finite element method (FEM) is introduced to study the saw-tooth chip formation in detail. By the way of Lagrange approach, adiabatic shear band (ASB) is simulated and the chip forming mechanism is interpreted by adiabatic shearing theory via the comparison of two models, one of which has a failure criterion and another not. The comprehensive comparison and analysis of chip morphology between simulation and experiment are also presented in this paper.

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33

Squarcella, Nicola, Christian Maria Firrone, Marco Allara, and Muzio Gola. "The importance of the material properties on the burst speed of turbine disks for aeronautical applications." International Journal of Mechanical Sciences 84 (July 2014): 73–83. http://dx.doi.org/10.1016/j.ijmecsci.2014.04.007.

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34

dos Santos, Bertolino Junio, Damásio Sacrini, Adilson Vitor Rodrigues, Geraldo Creci, and João Carlos Menezes. "Dynamic Characteristics of a 5-kN Thrust Gas Turbine Front Bearing Composed of a Vibration Absorber Element and Deep Groove Ball Bearing." Advanced Engineering Forum 47 (August 31, 2022): 43–53. http://dx.doi.org/10.4028/p-7916wb.

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Rolling bearings enable the development of high rotational speeds with a good load-bearing capacity and low frictional resistance. Therefore, rolling bearings can be used on a wide variety of rotating machines. This study investigated the dynamic stiffness and damping coefficients of the front bearing of a 5-kN thrust gas turbine. A Barden® 206(T) deep-groove ball bearing was the main part of the front bearing. Computational models were developed using MATLAB® for both the structural dynamics problem governed by Hertzian contact theory and the lubricated problem governed by elastohydrodynamic theory. In addition, the front bearing was composed of a vibration absorber element, which was also considered. Finite element analysis was performed on both the ball bearing and the vibration-absorbing element to assist in its final characterization. As the main results, the stiffness and damping dynamic coefficients of the front bearing were estimated and can be used to predict the rotordynamic behavior of the aeronautical gas turbine rotating set to avoid possible vibration problems during operation.

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35

Baker, J. P., E. A. Mayda, and C. P. van Dam. "Experimental Analysis of Thick Blunt Trailing-Edge Wind Turbine Airfoils." Journal of Solar Energy Engineering 128, no. 4 (July 19, 2006): 422–31. http://dx.doi.org/10.1115/1.2346701.

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An experimental investigation of blunt trailing-edge or flatback airfoils was conducted in the University of California, Davis aeronautical wind tunnel. The blunt trailing-edge airfoil is created by symmetrically adding thickness to both sides of the camber line of the FB-3500 airfoil, while maintaining the maximum thickness-to-chord ratio of 35%. Three airfoils of various trailing-edge thicknesses (0.5%, 8.75%, and 17.5% chord) are discussed in this paper. In the present study, each airfoil was tested under free and fixed boundary layer transition flow conditions at Reynolds numbers of 333,000 and 666,000. The fixed transition conditions were used to simulate surface soiling effects by placing artificial tripping devices at 2% chord on the suction surface and 5% chord on the pressure surface of each airfoil. The results of this investigation show that lift increases and the well-documented thick airfoil sensitivity to leading-edge transition reduces with increasing trailing-edge thickness. The flatback airfoils yield increased drag coefficients over the sharp trailing-edge airfoil due to an increase in base drag. The experimental results are compared against numerical predictions obtained with two different computational aerodynamics methods. Computations at bounded and unbounded conditions are used to quantify the wind tunnel wall corrections for the wind tunnel tests.

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36

Bravo, H., N. Ortega, R. Polvorosa, and I. Zamakona. "On the performance of Super Abrasive Machining (SAM) on small diameter cBN wheel wear." IOP Conference Series: Materials Science and Engineering 1193, no. 1 (October 1, 2021): 012011. http://dx.doi.org/10.1088/1757-899x/1193/1/012011.

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Abstract Electroplated cBN wheels have increased their importance in industry, mainly in camshaft, crankshaft and gearbox grinding in the automotive sector and in grinding of aeronautical turbine parts made from nickel superalloys. Possible new applications include Integrated Blade Rotors (IBRs), whose importance is increasing in new aeroengine configurations. Electroplated cBN wheels form retention without trueing or dressing and low wear make them suitable for this usage. However, few information is available about wear and resulting surface finish characteristics in the small diameter wheels needed for this application. In this study, data about wheel topography and wear and surface finishing of resulting surfaces is shown. Also, some hypothesis about the reasons for the higher-than-expected resulting surface finish are exposed.

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37

Szender, Marcin. "SCALED HIGH ANGLE RESEARCH VEHICLE SHARV) PROGRAM." Aviation 8, no. 1 (March 31, 2004): 13–17. http://dx.doi.org/10.3846/16487788.2004.9635864.

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A flight test research program employing a remotely piloted vehicle (RPV) within high angle of attack range has commenced at the Faculty of Power and Aeronautical Engineering of Warsaw University of Technology, Poland. The initial flights of the scaled model of the “Bielik” aircraft were made with the aim to correlate RPV and full‐scale flight stall and departure and spin controllability considering the effects of dynamic scaling laws and Reynolds number. The remotely controlled research aircraft, which is powered by a turbine jet engine and equipped with a flight data recording system, proved to be good source of stability and control data at relatively low cost and without additional risk. The research remotely piloted vehicle and results of its initial flights are presented in this paper.

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38

Wan, Yi, Qing Hua Song, and Zhan Qiang Liu. "Identification of Stability Lobes in High-Speed Milling Flexible Parts with Bull-Nose End Mills." Key Engineering Materials 443 (June 2010): 297–301. http://dx.doi.org/10.4028/www.scientific.net/kem.443.297.

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Flexible parts such as turbine blade, blisk and monolithic components are widely used in the aeronautical industry, and high Speed Machining (HSM) technology is used to increase productivity and reduce production costs. Chatter is an undesirable phenomenon in high speed machining processes because of deteriorative surface finish, early cutting tool failure and unexpected machine tool damage. It can be avoided in higher speed milling processes if stability lobes is determined. In this paper, a non-linear regenerative force model is applied to a bull-nose tool geometry in order to obtain the machine operation stability lobes. An analytical-experimental method is proposed to obtain the stability lobes during high speed milling flexible parts with bull-nose end mills. The method is calculated and validated.

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39

Song, Shu Fang, and Zhen Zhou Lu. "Line Sampling Reliability Analysis for Low Cycle Fatigue Life of Aeronautical Engine Disc Structure." Key Engineering Materials 324-325 (November 2006): 875–78. http://dx.doi.org/10.4028/www.scientific.net/kem.324-325.875.

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In engineering reliability analysis, the limit state equation is generally implicit and nonlinear, and large number basic random variables and small failure probability are associated. For this kind of reliability analysis, a novel numerical simulation is presented based on the combination of Markov Chain Simulation and line sampling. In the presented method, Markov Chain Simulation is used to draw samples in the failure domain rapidly, and important direction for the line sampling is determined by these samples. Then the line sampling technique is employed to take samples according to the important direction, and failure probability can be evaluated by line sampling with high efficiency. Comparing to the finite differential method for obtaining the important direction, higher accuracy and higher robustness of the important direction are obtained by the presented method. The application in the reliability analysis of low cycle fatigue life of aeronautical engine turbine disc structure, which is applied by multiple cyclic loads, shows that the presented line sampling combining with the Markov Chain Simulation is efficient and feasible.

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40

Teleginski, Viviane, Júlio César Gomes Santos, Daniele Cristina Chagas, Jéssica Fernanda Azevedo, Ana Claudia Costa Oliveira, and Getúlio de Vasconcelos. "Parameters Evaluation of Bond-Coat Deposited by CO₂ Laser Beam for Aeronautical Turbine Blades." Materials Science Forum 869 (August 2016): 685–88. http://dx.doi.org/10.4028/www.scientific.net/msf.869.685.

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The high temperature environments where aeronautical turbine blades are exposed makes mandatory the use of ceramic coatings. A bond coat comprised by a MCrAlY alloy (M=Co, Ni) is necessary to match the blade metallic substrate with the ceramic, also acting as a corrosion barrier. The laser treatment of metals and alloys is based in the surface local heating, followed by high cooling rates. The laser parameters such as scanning speed and laser power, plays an important role on the morphological, mechanical and chemical characteristics of the deposited material. In the present investigation, the NiCrAlY deposition was performed in stainless steel substrates with a CO2 laser beam. Different laser parameters of scanning speed and number of scanning cycles were implemented. The samples were characterized by optical microscopy and measurements of Vickers hardness. The results show that it is possible to achieve coatings with high hardness, free of pores or any pronounced defects, metallurgically bonded to the substrate.

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41

Nahum, Andrew. "Two-Stroke or Turbine? The Aeronautical Research Committee and British Aero Engine Development in World War II." Technology and Culture 38, no. 2 (April 1997): 312. http://dx.doi.org/10.2307/3107125.

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42

Liu, C. L., Z. Z. Lu, Y. L. Xu, and Z. F. Yue. "Reliability analysis for low cycle fatigue life of the aeronautical engine turbine disc structure under random environment." Materials Science and Engineering: A 395, no. 1-2 (March 2005): 218–25. http://dx.doi.org/10.1016/j.msea.2004.12.014.

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43

Alajmi, Amer, Fnyees Alajmi, Ahmed Alrashidi, Naser Alrashidi, and Nor Mariah Adam. "Application of Ultrasonic Atomization on a Micro Jet Engine Using Biofuel for Improving Performance." Processes 9, no. 11 (November 3, 2021): 1963. http://dx.doi.org/10.3390/pr9111963.

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Jet engines are commonly used in aeronautical applications, and are one of the types of gas turbine engines. The circulation of air releases heat energy to expand the volume of hot fluids and impact the turbine wheel to generate power of hot gases. The present study investigates the potential of using ultrasonic atomization technology to assist in the combustion process. An experimental rig was set up to determine the performance of jet engines using ultrasonic droplets. A gas analyzer was used to measure various greenhouse emissions of exhaust gas. The performance of the engine was tested under three load levels (high, medium, low), starting from 10 psi at a steady state, to the minimum value. A significant result was tested for a low value of nitrogen monoxide at the three levels of load, and a specific result was tested for an efficiency value of 2% at the three levels of load. Carbon dioxide was found to decrease at the low load level. The use of an ultrasonic atomization device to assist in the combustion process was useful in achieving engine efficiency of 1% and a reduction of 25% in carbon dioxide exhaust gas.

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44

Daniele, Elia, Matthias Schramm, Christof Rautmann, Mehdi Doosttalab, and Bernhard Stoevesandt. "An extension of a strong viscous–inviscid coupling method for modeling the effects of vortex generators." Wind Engineering 43, no. 2 (June 14, 2018): 175–89. http://dx.doi.org/10.1177/0309524x18780390.

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The aim of this work is to provide insights into the advantages and the limitations of the extension of a strong viscous–inviscid interactive code for modeling the effects of vortex generators, with focus on the calibration and validation for wind turbine airfoils. The proposed methodology relies on the approach proposed by other authors in the past and introduces an alternative formulation for the lag dissipation within the integral boundary-layer equations whose effects on the numerical prediction are evaluated. Besides the verification of the aeronautical test cases, particular attention is devoted to the validation of the results for several airfoils commonly used in wind turbine design. A blind test for airfoils from an industrial test case is conducted as well. Results show that the maximum lift coefficient can be well predicted by the present implementation, whereas the angle of maximum lift is a little higher than in wind tunnel measurements. Apart from that, the drag coefficients of airfoils with vortex generators cannot be predicted by the current implementation, but it is expected that the maximum lift and the stall angle of attack are more important in the design phase, since they determine power, loads, and noise.

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45

Apostolidis, Asteris, Nicolas Bouriquet, and Konstantinos P. Stamoulis. "AI-Based Exhaust Gas Temperature Prediction for Trustworthy Safety-Critical Applications." Aerospace 9, no. 11 (November 17, 2022): 722. http://dx.doi.org/10.3390/aerospace9110722.

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Data-driven condition-based maintenance (CBM) and predictive maintenance (PdM) strategies have emerged over recent years and aim at minimizing the aviation maintenance costs and environmental impact by the diagnosis and prognosis of aircraft systems. As the use of data and relevant algorithms is essential to AI-based gas turbine diagnostics, there are different technical, operational, and regulatory challenges that need to be tackled in order for the aeronautical industry to be able to exploit their full potential. In this work, the machine learning (ML) method of the generalised additive model (GAM) is used in order to predict the evolution of an aero engine’s exhaust gas temperature (EGT). Three different continuous synthetic data sets developed by NASA are employed, known as New Commercial Modular Aero-Propulsion System Simulation (N-CMAPSS), with increasing complexity in engine deterioration. The results show that the GAM can be predict the evolution of the EGT with high accuracy when using several input features that resemble the types of physical sensors installed in aero gas turbines currently in operation. As the GAM offers good interpretability, this case study is used to discuss the different data attributes a data set needs to have in order to build trust and move towards certifiable models in the future.

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46

CUI, Aiyong, Huakai WEI, Haodong LIU, Bin HU, and Hui YU. "Study on Microstructure and Properties of Aeronautical Nickel-Based Superalloy in Laser Directional Solidification." Materials Science 27, no. 2 (May 5, 2021): 155–60. http://dx.doi.org/10.5755/j02.ms.23522.

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FFor the directional solidification repair of blade damage in an aviation turbine, a directional-growth repair layer on the surface of a nickel-based superalloy was prepared using an Nd:YAG laser. The microstructure of the directional-growth repair layer was investigated using scanning electron microscopy and transmission electron microscopy. Its phase composition and corrosion resistance were also analyzed and tested. The results indicate that the grains in the repair zone solidified in the same direction as the substrate and formed continuous columnar crystals, which were arranged in an orderly manner. A small number of secondary dendritic cells were dispersed in the transverse direction of the columnar crystals. The phase composition was mainly composed of the α′-based phase, β-precipitated strengthening phase, MC carbide, and interdendritic α′/β eutectic phase. The corrosion kinetic curve of the repair zone changed linearly. The oxide film was uniform and dense, and was mainly composed of continuous granular oxide. The corrosion kinetic curve of the substrate conformed to the parabolic law. The oxide film was composed of loose and bulky granular grains, which were stacked in the shape of regular polyhedra and distributed in the form of an island.

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47

Song, Shu Fang, and Zhen Zhou Lu. "Improved Line Sampling Reliability Analysis Method and its Application." Key Engineering Materials 353-358 (September 2007): 1001–4. http://dx.doi.org/10.4028/www.scientific.net/kem.353-358.1001.

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For reliability analysis of implicit limit state function, an improved line sampling method is presented on the basis of sample simulation in failure region. In the presented method, Markov Chain is employed to simulate the samples located at failure region, and the important direction of line sampling is obtained from these simulated samples. Simultaneously, the simulated samples can be used as the samples for line sampling to evaluate the failure probability. Since the Markov Chain samples are recycled for both determination of the important direction and calculation of the failure probability, the computational cost of the line sampling is reduced greatly. The practical application in reliability analysis for low cycle fatigue life of an aeronautical engine turbine disc structure under 0-takeoff-0 cycle load shows that the presented method is rational and feasible.

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48

Odgers, J., D. Kretschmer, and G. F. Pearce. "The Combustion of Droplets Within Gas Turbine Combustors: Some Recent Observations on Combustion Efficiency." Journal of Engineering for Gas Turbines and Power 115, no. 3 (July 1, 1993): 522–32. http://dx.doi.org/10.1115/1.2906739.

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For many years investigators studying the combustion behavior within gas turbines have presumed droplet size to play a very important role in defining combustion efficiency. Recently a very large number of experiments have been conducted jointly by Laval University and the Aeronautical Research Laboratory in Melbourne. In the course of these investigations, over a wide range of operating conditions, a single combustor has been investigated using three different Simplex atomizers at each of the conditions for three fuels. In addition, the same combustor has been used to investigate a very wide range of fuels (87) at ambient inlet conditions. The measured combustion efficiencies show no measurable effects due to droplet size, although volatility effects have been noted (measured as TAV). It is thought that these effects are reflected in terms of a transfer number and related to diffusional phenomena, rather than evaporative phenomena. A great number of experimental data are reviewed, and in addition to showing the absence of effects of droplets, a small section deals with the precision of experimental values of combustion efficiency and how it might influence models predicting combustion efficiency, especially with respect to possible future pollution requirements.

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49

Takahashi, Renata Jesuina, J. M. K. Assis, Francisco Piorino Neto, A. M. Mello, and Danieli Aparecida Pereira Reis. "Sintering Study of NiCrAlY." Materials Science Forum 899 (July 2017): 478–82. http://dx.doi.org/10.4028/www.scientific.net/msf.899.478.

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In ceramics TBC ́s (thermal barrier coating) the MCrAlY layer is used like a bond coat between nickel superalloys and zirconia ceramics used in aeronautical turbine blades. However the oxidation of this layer is an important step to obtain an Al2O3 as TGO (thermally grown oxide), on which the zirconia ceramics is placed on to protect the turbine blades from high temperatures and oxidizers and corrosive gases generated during the burning of the fuel. To understand the oxidation process, parallel and flat surface samples are required. These surfaces will allow characterization, especially the tribologic ones. The samples were prepared through different process and sintering routes. Powders of NiCrAlY with and without binder were uniaxially pressed from 100 MPa to 250 MPa. Isostatically pressed samples at 300 MPA were also prepared. The samples were sintered in the air, at 10-7 Torr and hot uniaxially pressed at 10 MPa. The sintering temperature started at 800 °C up to 1200 °C during one hour. The best result was from the hot pressed samples between 1000 °C and 1150 °C. Above this temperature the process became complicated and started melting at 1200 oC. Mainly due to the spherical shape of NiCrAlY particles, it was not possible to get good samples when sintering in the air.

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50

Bray, K. N. C., and N. Riley. "John Frederick Clarke. 1 May 1927 — 11 June 2013." Biographical Memoirs of Fellows of the Royal Society 60 (January 2014): 87–106. http://dx.doi.org/10.1098/rsbm.2014.0012.

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Flying, and an enthusiasm for aviation, motivated John Clarke’s early career choices: he flew Fairey Fireflys in the Fleet Air Arm, worked in the Gas Turbine Division of Armstrong Siddeley Motors, and studied aeronautical engineering at Queen Mary College, where he graduated with first-class honours. He stayed on there to do a PhD, and then worked at English Electric, before moving to Cranfield in 1958. John Clarke’s many important publications, mainly in the general area of chemically reacting flows, cover a wide range of topics including flames, ignition processes, shock waves and detonations, the dynamics and physics of burning gases and internal ballistics, to name but a few. In all of his contributions to his subject it is perhaps too easy to overlook the individual. He had a delightful sense of humour, wore his distinctions lightly and was a most generous and friendly man.

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Journal articles on the topic 'Aeronautical turbine'

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