| 1. |
- Arnal, D., et al.
(author)
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Supersonic laminar flow control studies in the SUPERTRAC project
- 2006
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In: ICAS-Secretariat. - 9781604232271 ; , s. 1014-1023
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Conference paper (peer-reviewed)abstract
- The global objective of the SUPERTRAC project is to explore the possibilities to delay laminar-turbulent transition on supersonic aircraft wings. The following techniques are investigated: micron-sized roughness elements, anti-contamination devices, suction and shape optimization. This paper provides an overview of the project and describes in more detail the numerical investigations performed during the first year in order to design two wind tunnel models. These models will be used to assess the capabilities of the first three techniques listed above.
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| 2. |
- Austrin, Lars, et al.
(author)
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A new high power density generation system
- 2006
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In: ICAS-Secretariat, 25th Congress of the International Council of the Aeronautical Sciences 2006. - 9781604232271 ; , s. 3600-3604
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Conference paper (peer-reviewed)abstract
- A trend of increased Electric Power in Aircraft stresses the need of robust, low weight systems with low losses. New hard and soft magnetic materials have made it feasible to work with high speed and high frequency. Applications of new soft magnetic materials and hard magnetic materials like NeFeB magnets have enabled high density power generation systems. A new concept comprising a high speed PM-generator system and a magnetic amplifier control is presented. Magnetic amplifiers are used in the power supply of the Electronic Flight Control System in the Swedish "Gripen" fighter-aircraft. This technology is attractive in More Electric Aircraft (MEA) systems due to the possibility to achieve a compact, robust and a highly reliable system with low losses. Applications of new soft magnetic materials, such as amorphous magnetic alloys, have enabled the use of magnetic amplifier (magamp) technology in the design of competitive electric power converters. This paper presents a studied design on a 20-40 kW generator system including a +/- 270V controlled output, performed by magnetic amplifier technology. This work addresses the power generator, and the power converter. High speed PM-generators are offering high power density. The impact of operating a generation system with higher frequency and an increasing number of poles as well as the advantages with new soft magnetic materials is studied. The iron losses and the copper losses are analyzed for the generator, and the power converter.
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| 3. |
- Austrin, L., et al.
(author)
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Analysis of a feasible pulsed-power supply system for an Unmanned Aerial Vehicle
- 2006
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In: ICAS-Secretariat. - 9781604232271 ; , s. 3605-3612
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Conference paper (peer-reviewed)abstract
- More Electric Aircraft technology enables the power supply of electric energy weapons such as high-power microwave and laser weapons. Aspects of electric power generation, energy storage, distribution and pulse-conditioning systems for the power supply of directed energy weapons in Unmanned Aerial Vehicle are addressed in this paper. A trend in aircraft design is to electrify more parts of the aircraft via the concept of More Electric Aircraft (MEA) and its technology which allows for increased electric power consumption. Thus, MEA technology enables the power supply of weapons and protection systems that are using electric energy. Among these devices directed energy weapons such as high-power microwave (HPM) and laser weapons are feasible. Such systems require high power pulsed electric energy with, thus imposing new requirements of on-board power supplies. In the demonstrated concept it is important to analyze power losses and efficiency as well as weight and volume in order to evaluate the possibility to adapt the system in an UAV.
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| 4. |
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| 5. |
- Crippa, Simone, et al.
(author)
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Initial steady/unsteady CFD analysis of vortex flow over the VFE-2 delta wing
- 2006
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In: 25th Congress of the International Council of the Aeronautical Sciences, 3-8 September 2006, Hamburg, Germany. - 9781604232271 ; , s. 883-892
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Conference paper (peer-reviewed)abstract
- This study is aimed at assessing the application of the latest unstationary CFD method, Detached- Eddy Simulation (DES), to simulate the flowfield around blunt leading edge delta wings. For this purpose, the Second International Vortex Flow Experiment (VFE-2) 65° sweep delta wing model was used to perform numerical investigations at a Reynolds number of 6 million, Mach number of 0.4 and angles of attack of 18.5° and 23°. As the nature of this study is mainly exploratory, various numerical grids have been used. The results confirm the maturity of Reynolds averaged Navier-Stokes (RANS) methods but also the problems of DES to predict free separation and the grid sensitivity of this model.
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