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Doelstelling: De doelstelling van de scriptie was om na te gaan in hoeverre de schrijvers van de serie de feiten waarheidsgetrouw hebben weergegeven. Door naar de serie te kijken, krijgen de kijkers een bepaald beeld van hoe het er in het Witte Huis aan toe gaat. De bedoeling was om na te gaan of dit beeld strookt met de werkelijkheid. Middelen of methode: Ik selecteerde een aantal culturele en politieke referenties uit vier episodes van het tweede seizoen. Van die vier episodes kon ik de officiële scripts bemachtigen. Het aantal culturele en politieke referenties moest wel gereduceerd worden omdat de serie er vol van zit. Ik heb diegene geselecteerd die het interessants waren.Van die referenties zocht ik eerst algemene informatie om de referentie in te leiden en de lezer van de scriptie vertrouwd te maken met het onderwerp. Daarna volgt het resultaat van mijn onderzoek waarin staat hoe het er in de werkelijkheid aan toe gaat en wordt er een vergelijking gemaakt tussen fictie en werkelijkheid. Resultaten: De schrijvers zijn heel gedetailleerd te werk gegaan bij het schrijven van de dialogen. Vrijwel alle referenties zijn volledig waarheidsgetrouw weergegeven. Er zijn soms een paar elementen aangepast maar dit is nu eenmaal nodig om de serie aantrekkelijk te houden voor de kijkers. De namen van de personages en van personen uit de vriendenkring van die personages zijn wel fictief maar het is vrijwel onmogelijk hiervoor echte namen te gebruiken. Op die manier zou de serie ook te veel politiek gekleurd zijn en er is nu al kritiek van bepaalde Republikeinen dat de serie niet meer is dan liberale propaganda.

Het Witte Huis. --- Maatschappij en instellingen. --- Televisie serie. --- The West Wing. --- Verenigde Staten.

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In this thesis, a review of the history of blended wing bodies has been done and the various advantages that blended wing bodies offer has been exposed. The increased aerodynamic per- formance as well as noise reduction assures blended wing bodies a bright future.
The goal of the thesis was to aerodynamically study a blended wing body UAV and propose a new enhance geometry.
To do that, two different methods of analysis were first validated through comparison with expe- rimental results of simple geometries (NACA wings). Those two methods included a low-fidelity one, PanAir and a higher fidelity one, SU2. PanAir results turned out to be quite accurate pro- vided that the drag coefficient was corrected. Some limitations of PanAir have, however, been highlighted namely when it was applied to configurations comprising flaps. SU2 showed better results but its computation time was much more important.
A detailed analysis of the baseline design of the UAV was then performed. Different aerody- namic coefficients were investigated as well as the influence of parameters of the flow. The influence of sideslip angle, control surfaces and propulsion has been studied.
Once the baseline geometry had been analysed, a parametric model of the geometry has been built. The idea was to change the geometry in order to improve the lift to drag ratio. First, the different parameters susceptible of being changed were studied separately to define the final set of varying parameters and their range of values.
A combination of the different parameters led to the study of 1024 different cases that were all compared to one another in order to find the one that maximized the lift to drag ratio while maintaining the required lift. A new geometry has thus been proposed.
The new geometry has been studied and compared to the old one to assess if it improved the aerodynamic performance. It turned out the new geometry induced an increase of 7% of the lift to drag ratio. The behaviour of the UAV when facing crosswind appeared to also be improved.
Finally, a sensitivity analysis on the Reynolds was performed to see if a future wind tunnel test campaign on a reduced size model could be possible. Trends showed that it was safe to analyse the UAV at different Reynolds number when the presence of thrust was ignored. The introduction of thrust led to some dependencies on the Reynolds pointing to the fact that a wind tunnel test should be performed cautiously.

UAV --- Blended wing body --- Aerodynamic behaviour --- Ingénierie, informatique & technologie > Ingénierie aérospatiale

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The flutter, is one of the most complex and dangerous aeroelastic phenomena. Nowadays, the certification authorities have to guarantee the non-appearance of this phenomenon, in such a way that the safety of the aircrafts is not compromised. The preliminary design of any aircraft includes an estimate of the flutter speed.
This thesis focuses on studying the estimation of the flutter speed through several methods, including numerical and experimental approaches. The main target is the discussion of the results and the possibility to develop an accurate method to properly predict the flutter speed and its characteristics in the near future. Three different methods are used in this thesis; empirical formula, numerical and experimental methods, where the differences between the experimentation and theory will be commented. 
The combination of different numerical methods as Finite Elements Method and Vortex Lattice Method is used simultaneity alongside wind tunnel tests. Moreover, an empirical formula based on the geometrical parameters is analysed and commented in an attempt to discover and prove new ways to develop this concept of flutter acquisition. Finally, some range conditions for the validity of this empirical formula are defined in base of a comparison to the other methods.

flutter --- aeroelasticity --- wind tunnel --- wing --- FEM --- VLM --- experimental aerodynamics --- damping --- frequency --- Fast Fourier Transform --- Ingénierie, informatique & technologie > Ingénierie aérospatiale

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Certification of an aircraft is a long and demanding process required by airworthiness requirements of international organisms such as the European Aviation Safety Agency. Being intended to flight schools market, the general aviation Sonaca 200 aircraft has to fulfil huge amount of prerequisites defined by the Certification Specification for Very Light Aeroplane. Among the standards, free-flutter conditions have to be respected and demonstrated by the manufacturer, Sonaca Aircraft. This work concerns the aerodynamic and flutter analyses of a simplified wing model of the Sonaca 200 aircraft. The former study in performed thanks to a
time-stepping implementation, developed by KATZ J., of the unsteady Vortex Lattice method. The algorithm is adjusted in order to provide a minimum convergence time to reach a well-defined results accuracy. The method based on the incompressible potential flow theory is adapted to the S200 wing and validated through a comparison with the Sonaca Aircraft aerodynamic results for a flight situation encountered at dive speed and limit load factor. The parallel is carried out in terms of total and spanwise aerodynamic coefficients induced by the lifting surface. The validation of the first method leads to the consideration of the flutter analysis.
The second implementation of the unsteady Vortex Lattice method is developed by DIMITRIADIS G. in the frequency domain. This development, combined with a condensate finite element model of the wing, allows to compute the unsteady aerodynamic loads through a Generalised Force Matrix. The modal equations of motion are then solved with the help of a Newton-Raphson scheme and a p-k method. The second wing mode caused the instability leading to the flutter phenomenon caused by a lack of damping at high speed. The flight envelop of the wing is free from flutter in control surfaces blocked and empty fuel tanks setup. Altitude has an influence on the flutter speed and frequency. The critical case appears for a service ceiling altitude on a wing
with its implemented wing-tips. Static wing deflections are derived from the method. Further improvements of the aeroelastic model can be performed in order to verify the free-flutter behaviour of the whole Sonaca 200 aircraft in all possible flight conditions.

Vortex --- Flutter --- unsteady --- wing --- aerodynamics --- p-k method --- Sonaca 200 --- Generalised Force Matrix --- Steady --- Deflection --- Finite element model --- Mode shape --- Equation of motions --- Starting vortex --- Wake --- Wing-tips --- Winglets --- Aeroelasticity --- Damping ratio --- Frequency --- Unsteady Vortex Lattice Method --- Ingénierie, informatique & technologie > Ingénierie aérospatiale