| 1. |
- Amadori, Kristian, et al.
(författare)
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Multidisciplinary Optimization of Wing Structure Using Parametric Models
- 2013
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Aircraft design is an inherently multidisciplinary activity that requires integrating different models and tools to reach a well-balanced and optimized product. At Linköping University a design framework is being developed to support the initial design space exploration and the conceptual design phase. Main characteristics of the framework are its flexible database in XML format, together with close integration of automated CAD and other tools, which allows the developed geometry to be directly used in the subsequent preliminary design phase. In particular, the aim of the proposed work is to test the framework by designing, optimizing and studying a transport aircraft wing with respect to aerodynamic, geometry, structural and accessability constraints. The project will provide an initial assessment of the capability of the framework, both in terms of processing speed and accuracy of the results.
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| 2. |
- Jouannet, Christopher, et al.
(författare)
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Design and Flight Testing of a Solar Powered Aircraft, a Student Challenge
- 2013
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The presented work considers designing, building and flight testing a solar poweraircraft as a student project. The goal is to allow student to participate in an aircraft projectfrom design to flight test in order to acquire aircraft design knowledge from theoretical andpractical means. A first theoretical part consists of creating a sizing program for studyingdifferent concepts. Then the gathered knowledge will result in the realization of a flyingdemonstrator. This was realized during a student project over a 5 month period
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| 3. |
- Melin, Tomas, 1975-
(författare)
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Parametric Airfoil Catalog Part I, Archer A18 to Göttingen 655 : An Aerodynamic and Geometric Comparison Between Parametrized and Point Cloud Airfoils
- 2013. - 1
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- A fundamental part of aircraft design involves wing airfoiloptimization, establishing an outer shape of the wing which has good aerodynamic performance for the design mission, good internal volume distribution for fuel and systems and which also serves as an efficient structural member supporting the load of the weight of the aircraft. The underlying idea with this parametrization is to couple an appropriate number of parameters, balancing the need of geometric accuracy with the necessity of few airfoil parameters in order to facilitate en expedient optimisation, with the intrinsic value of having parameters that makes sense for a human; such as thickness, camber and trailing edge thickness. Several approaches to parametrization of wing proles can be found in the literature. Airfoils can be described by point clouds as done in most airfoil libraries. The number of parameters is twice as large as the number of points used (x and y coordinates) and in the case of aerodynamic optimization this parametrization will most certainly be not well behaved, since no smoothing function is included and must therefore be employed. Other problems may arise for the fact that the airfoils sometimes are defined with too few coordinate points and/or too few decimals, a problem occurring especially with old airfoils. On the other hand, the design space that this kind of parametrization allows representing is extremely large, as any and all shapes can be reproduced, even degenerate ones. Airfoils can also be represented by mathematical functions. Among the most common representatives of thiscategory are indeed the NACA 4-, 5- and 6-digits formulations. Compared to point clouds, they could be said to represent the opposite case: they are very well behaving parametrizations, but they cannot cover avery large design space, since they only provide four to six parameters respectively to be tuned. The NACA 4digit series is particularly interesting as the parametersare a part of the name of the airfoil. In the case of the 5- and 6 digit series, the name is instead constructed from the airfoils aerodynamic characteristic and geometry. Another known set of theoretically defined airfoils are the Joukowski profiles [4]. Using the conformal mapping method, airfoils with a round nose and sharp trailing edge can be represented. Sadly the method is not to recommend for trying to match known airfoils and the design space it describes is quite confined to airfoils with often poor performances.
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| 4. |
- Melin, Tomas, 1975-
(författare)
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Parametric Airfoil Catalog, Part II: Göttingen 673 to YS930 : An Aerodynamic and Geometric Comparison Between Parametrized and Point Cloud Airfoils
- 2013
-
Bok (övrigt vetenskapligt/konstnärligt)abstract
- A fundamental part of aircraft design involves wing airfoiloptimization, establishing an outer shape of the wing which has good aerodynamic performance for the design mission, good internal volume distribution for fuel and systems and which also serves as an efficient structural member supporting the load of the weight of the aircraft. The underlying idea with this parametrization is to couple an appropriate number of parameters, balancing the need of geometric accuracy with the necessity of few airfoil parameters in order to facilitate en expedient optimisation, with the intrinsic value of having parameters that makes sense for a human; such as thickness, camber and trailing edge thickness. Several approaches to parametrization of wing proles can be found in the literature. Airfoils can be described by point clouds as done in most airfoil libraries. The number of parameters is twice as large as the number of points used (x and y coordinates) and in the case of aerodynamic optimization this parametrization will most certainly be not well behaved, since no smoothing function is included and must therefore be employed. Other problems may arise for the fact that the airfoils sometimes are defined with too few coordinate points and/or too few decimals, a problem occurring especially with old airfoils. On the other hand, the design space that this kind of parametrization allows representing is extremely large, as any and all shapes can be reproduced, even degenerate ones. Airfoils can also be represented by mathematical functions. Among the most common representatives of thiscategory are indeed the NACA 4-, 5- and 6-digits formulations. Compared to point clouds, they could be said to represent the opposite case: they are very well behaving parametrizations, but they cannot cover avery large design space, since they only provide four to six parameters respectively to be tuned. The NACA 4digit series is particularly interesting as the parametersare a part of the name of the airfoil. In the case of the 5- and 6 digit series, the name is instead constructed from the airfoils aerodynamic characteristic and geometry. Another known set of theoretically defined airfoils are the Joukowski profiles [4]. Using the conformal mapping method, airfoils with a round nose and sharp trailing edge can be represented. Sadly the method is not to recommend for trying to match known airfoils and the design space it describes is quite confined to airfoils with often poor performances.
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| 5. |
- Melin, Tomas, 1975-, et al.
(författare)
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Parametric wing profile description for conceptual design
- 2011
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Ingår i: CEAS 2011 Proceedings.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- A fundamental part of aircraft design involves the wing airfoil optimization, establishing an outer shape of the wing which has good aerodynamic performance, good internal volume distribution for fuel and systems and which also serves as an efficient structural member supporting the weight of the aircraft. As for all optimization tasks, the complexity of the problem is directly coupled to the parameterization of the geometry. Of highest relevance are the number of parameters and the number of additional constraints that are required to ensure valid modeling.This paper proposes a parameterization method for two dimensional airfoils, aimed at providing a wide design space, while at the same time keeping the number of parameters low. With 15 parameters defining the wing profile, many of the existing airfoils can be modeled with close tolerance.Several approaches to parameterization of wing profiles can be found in the literature. Airfoils can be described by point clouds as done in most airfoil libraries [1]. The number of parameters is twice as large as the number of points used (x and y coordinates) and in the case of aerodynamic optimization this parameterization will most certainly be not well behaved, since no smoothing function is included and must therefore be added. Other problems may arise for the fact that the airfoils sometimes are defined with too few coordinate points and/or too few decimals, a problem occurring especially with old airfoils. On the other hand, the design space that this kind of parameterization allows representing is extremely large, as any and all shapes can be reproduced, even degenerate ones.
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| 6. |
- Melin, Tomas, 1975-
(författare)
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Validation of a numerical simulation tool for aircraft formation flight
- 2013
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Ingår i: Proceedings of the 4:th CEAS Conference in Linköping 2013. - 9789175195193 ; , s. 623-629
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The use of formation flight for increased fuel efficiency has received a lot of attention in the last couple of years.This paper covers a numerical simulation of a NASA test flight utilizing a formation of two F18A Hornet aircraft. The numerical simulation was made using an adapted version of the vortex lattice method TORNADO, allowing for several aircraft to be simulated in a trimmed condition. The numerical results showed good agreement with the flight test data. Some discrepancies due to the numerical model not covering viscous diffusion was found as expected but not quantified or analyzed.
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| 7. |
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PROCEEDINGS of the 4:th CEAS conference in Linköping, 2013
- 2013
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Proceedings (redaktörskap) (refereegranskat)abstract
- Europe has a strong and proud tradition in aerospace and astronautics, which indeed is a very important area for Europe. It represents a substantial business domain, but maybe equally important, it is also a driver for technology development and innovation that benefits the society as a whole. One of Europe’s greatest challenges is about independence, in order to keep and maintain capabilities within the complete set of technologies needed as a foundation for a sustainable aerospace industry in Europe. This is important when Europe has to look at the next generation of Air Power. It is also fundamental for Europe to be an attractive partner in international projects conducted with global collaboration.CEAS – Council of European Aerospace Societies – is an organisation bringing European national aerospace organisations together for increased international strength. Today, CEAS comprises sixteen member organisations with roughly 35,000 individual members. CEAS hosts biennial conferences on aeronautics in Europe where CEAS 2013 in Linköping is the fourth after Venice 2011, Manchester 2009 and Berlin 2007.
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