| 1. |
- Avellan, Rickard, 1976, et al.
(författare)
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Boxprop, a forward-swept joined-blade propeller
- 2013
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Ingår i: ISABE-2013-1108.
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Konferensbidrag (refereegranskat)abstract
- This article describes the Boxprop, a new high-speed propeller concept with forward swept joined-blade for future transport aircraft applications. Both numerical and experimental investigations of the joined-blade propeller were carried out at GKN Aerospace and Chalmers University in order to answer some of the fundamental questions relating to aerodynamic performance and mechanical integrity. The results show that the Boxprop concept works as intended and in particular that rapid prototyping methods using polymeric materials are suitable for early product development, even for functional testing of high speed propellers. Furthermore, based on the positive outcome of the experimental work described in this article, the next development step can be started by initiating the design of the counter-rotating Boxprop and wind tunnel test stand to proof the concept at TRL 3.
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| 2. |
- Giuliani, Fabrice, et al.
(författare)
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PULSE DETONATION AS AN OPTION FOR FUTURE INNOVATIVE GAS TURBINE COMBUSTION TECHNOLOGIES: A CONCEPT ASSESSMENT
- 2010
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Ingår i: 27TH INTERNATIONAL CONGRESS OF THE AERONAUTICAL SCIENCES Proceedings.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- A study on innovative combustion system for future aeroengine core concepts is done in the frame of the NEWAC project (EU FP6, AIP5-CT-2006-030876). A part of the high pressure core is replaced by a pulse detonation combustor. The ambition is to achieve a technical leap in TSFC reduction, or alternatively a lighter engine. In order to provide technical assessments on both the feasibility and performance of such a concept, specific tools were developed at TU Graz, Austria and Chalmers University, Sweden. The study emphasises the impact of flow intermittency on the direct environment of the pulse detonation combustor, and on the performance of a hybrid turbofan. A literature survey establishes the state of the art on pulse detonation technologies. Numerical tools for CFD calculation and performance analysis are presented. A concept assessment with a TSFC reduction by 5% in comparison to a conventional cycle is derived.1 General IntroductionThe need for more efficient and environment friendly engines is tending towards new methods of combustion. Although new injections systems currently in development, like LPP (Lean Premixed Prevaporised), RQL (Rich burn Quick quench Lean burn) and LDI (Lean Direct Injection), are promising a reduction in pollutant emission there is also the trend to look for innovative combustion methods to lower in addition fuel consumption. One premising way to reduce thrust specific fuel consumption (TSFC) is to use pulse detonation [6].A study on innovative combustion system for future aeroengine core concepts is done in the frame of the NEWAC project. A part of the high pressure core of a conventional aeroengine is replaced by a pulse detonation combustor. A medium-range two-spool turbofan is taken as a baseline for a back-to-back comparison.Pulse detonation (PD) is attractive because of its potential for higher thermal efficiency.
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| 3. |
- Grönstedt, Tomas, 1970, et al.
(författare)
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First and Second Law Analysis of Future Aircraft Engines
- 2013
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Ingår i: ASME Turbo Expo, 2013. - 9780791855133 ; 2:GT2013-95516
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Konferensbidrag (refereegranskat)abstract
- An optimal baseline turbofan cycle designed for a performance level expected to be available around year 2050 is established. Detailed performance data are given in take-off, top of climb and cruise to support the analysis. Losses are analyzed based on a combined use of the first and second law of thermodynamics, to establish a basis for discussion on future radical engine concepts and to quantify loss levels of very high performance engines. In the light of the performance of the future baseline engine, three radical cycles designed to reduce the observed major loss sources are introduced. The combined use of a first and second law analysis of an open rotor engine, an intercooled recuperated engine and an engine working with a pulse detonation combustion core is presented. In the past, virtually no attention has been paid to the systematic quantification of the irreversibility rates of such radical concepts. Previous research on this topichas concentrated on the analysis of the turbojet and the turbofan engine. In the framework developed, the irreversibility rates are quantified through the calculation of the exergy destruction per unit time. A striking strength of the analysis is that it establishes a common currency for comparing losses originating from very different physical sources of irreversibility. This substantially reduces the complexity of analyzing and comparing losses in aero engines. In particular, the analysis sheds new light on how the intercooled recuperated engine establishes its performance benefits.
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| 4. |
- Grönstedt, Tomas, 1970, et al.
(författare)
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First and Second Law Analysis of Future Aircraft Engines
- 2014
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Ingår i: Journal of Engineering for Gas Turbines and Power. - : ASME International. - 1528-8919 .- 0742-4795. ; 136:3
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Tidskriftsartikel (refereegranskat)abstract
- An optimal baseline turbofan cycle designed for a performance level expected to be available around year 2050 is established. Detailed performance data are given in take-off, top of climb, and cruise to support the analysis. The losses are analyzed, based on a combined use of the first and second law of thermodynamics, in order to establish a basis for a discussion on future radical engine concepts and to quantify loss levels of very high performance engines. In light of the performance of the future baseline engine, three radical cycles designed to reduce the observed major loss sources are introduced. The combined use of a first and second law analysis of an open rotor engine, an intercooled recuperated engine, and an engine working with a pulse detonation combustion core is presented. In the past, virtually no attention has been paid to the systematic quantification of the irreversibility rates of such radical concepts. Previous research on this topic has concentrated on the analysis of the turbojet and the turbofan engine. In the developed framework, the irreversibility rates are quantified through the calculation of the exergy destruction per unit time. A striking strength of the analysis is that it establishes a common currency for comparing losses originating from very different physical sources of irreversibility. This substantially reduces the complexity of analyzing and comparing losses in aero engines. In particular, the analysis sheds new light on how the intercooled recuperated engine establishes its performance benefits.
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| 5. |
- Larsson, Linda, 1981, et al.
(författare)
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A Conceptual Design Study of an Open Rotor Powered Regional Aircraft
- 2014
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Ingår i: ASME Turbo Expo: Turbine Technical Conference and Exposition, Dusseldorf, GERMANY. JUN 16-20, 2014. - 9780791845578 ; , s. V01AT01A023-
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Konferensbidrag (refereegranskat)abstract
- Today many of the routes between small to medium sized airports and large hubs are operated by regional aircraft, powered by turboprop or turbofan engines. In the future the open rotor engine might provide an alternative option. The open rotor would combine the possibility of high cruise speed with high propulsive efficiency. Also, since the open rotor essentially is a turboprop with the possibility to fly fast, there is a benefit of high specific range at low cruising speeds, thus giving it a wide range cruise operation.In this paper a regional aircraft for 70 passengers and 3000 km range is studied. The aircraft is evaluated with both a counter rotating open rotor and a turbofan engine. Aircraft design parameters such as wing area and sweep are varied together with engine parameters such as engine power and propeller disc loading.Results show that the open rotor aircraft has a 17.0 % higher specific range at the optimal cruise Mach number compared to the turbofan aircraft. For higher speeds, at Mach 0.78, the difference is reduced to 15.0 %. The long range cruise Mach number is around Mach 0.7 for the open rotor aircraft while for the turbofan aircraft it is slightly higher, around Mach 0.72.
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| 6. |
- Larsson, Linda, 1981, et al.
(författare)
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EFFECTS OF DIFFERENT PROPELLER MODELS ON OPEN ROTOR FUEL CONSUMPTION
- 2013
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Ingår i: International Society for Airbreathing Engines, ISABE, Busan, South Korea, 2013.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- In this study three different ways to represent a counter rotating propeller are evaluated. One where a map for a single rotating propeller is used, one where most of the swirl losses are excluded from the original map, and one where swirl losses are excluded and the position of the maximum efficiency is determined by the design disc loading.The two methods using the reduced swirl maps generate similar trends with similar size propellers for the optimal design and similar fuel burn figures. If the original single rotating map is used to represent counter rotating propellers the trends are significantly changed and are viewedto be unphysical. The optimal size propeller is then closer to 4.5 m rather than 3.5 meters. With the maps where a reduction in swirl losses are accounted for, the trends show a slightly decreasing fuel consumption with decreasing tip speed. If the single rotating propeller map is used there is an opposite trend and it is of higher magnitude.
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| 7. |
- Lundbladh, Anders, 1964, et al.
(författare)
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Transforming Propulsion Installation for Commercial Aircraft
- 2013
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Ingår i: ISABE-2013-1434.
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Konferensbidrag (refereegranskat)abstract
- The architecture of modern subsonic transport aircraft has converged to almost exclusively use engines in under wing nacelles. Although highly functional and successful in use, further reduction of fuel consumption with this configuration is progressively harder. The fuel consumption associated with nacelle weight and drag may in future aircraft using large low pressure ratio fans amount to 15% of the total. To achieve higher propulsive efficiency high speed propellers, distributed fans and boundary layeringestion have been proposed. The nacelle shape of currentinstallations is a compromise between the different requirements set from the varying flight speedover a flight mission. In the present paper, threeideas of shape changing, transforming elements in thepropulsion integration will be presented: adaption of a low drag nacelle to low speed conditions, mission variable noise shielding, and deployable propulsors.
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