Stuttgart, Univ., Diss., 2006.

Thesis (M.S.)--Auburn University, 2007. / Abstract. Vita. Includes bibliographical references.

Dissertation (Ph.D.)--University of Toledo, 2009. / Typescript. "Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Engineering." Bibliography: leaves 51-53.

Thesis (Ph. D.)--University of Missouri-Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves 179-185). Also available on the Internet.

Thesis--Auburn University, 2009. / Abstract. Vita. Includes bibliographical references (p. 53-55).

Thesis (Ph. D.)--University of Missouri-Columbia, 1998. / Typescript. Vita. Includes bibliographical references (leaves 179-185). Also available on the Internet.

Thesis (M.S.)--Naval Postgraduate School, 1985. / Cover title. "September 1985." Includes bibliographical references (p. 104-108).

Orientador: Rodolpho Vilhena de Moraes / Banca: Maria Cecília França de Paula Santos Zanardi / Banca: Valdemir Carrara / Resumo: Devido à sua dependência a um grande número de parâmetros de difícil determinação, o cálculo de coeficiente de arrasto para satélites artificiais torna-se extremamente complexo. Teorias, como as desenvolvidas por Schamberg e Sehnal levam em consideração o coeficiente de acomodação térmico e os ângulos de incidência e reflexão das moléculas na superfície do satélite. Outras teorias como a de Stalder e Zurick utilizam nas suas formulações os seguintes parâmetros: a razão entre as velocidades do satélite e das moléculas da atmosfera, o coeficiente de acomodação térmico, o ângulo de ataque e a razão entre as temperaturas da superfície do satélite e a temperatura das moléculas incidentes. Neste trabalho algumas teorias para o cálculo do coefienciente de arrasto são analisadas comparativamente. Exemplos são exibidos, utilizando como modelo os satélites SCD1, SCD2 e CBERS1. / Abstract: Drag coefficient computation for artificial satellite is extremely complex due to its dependence on several parameters that are difficult to determine. Some theories for drag coefficient computation, such as those developed by Schamberg and Sehnal, took into account the thermal accommodation coefficient and the incident and reflection angles of the molecules in the satellite surface. Others theories, such as the Stalder and Zurick theories, use in their formulations the following parameters: the ratio between the satellite velocity and the velocity of the molecules in the atmosphere, the thermal accommodation coefficient, the attack angle and the ratio between the temperatures of the satellite surface and of the incident molecules. In this work some theories for drag coefficients computation are comparatively analyzed. Examples are exhibited using the satellites SCD1, SCD2 and CBERS1 as models. / Mestre

Dans Trouble dans le genre (1990), Judith Butler affirme que le drag démontre la structure imitative du genre. Si, dans le sens commun, le drag est souvent rattaché à la performance travestie, nous allons voir avec Butler qu’il recouvre un ensemble complexe de pratiques corporelles (rôles sexuels, modifications corporelles, etc.). Alors, comment s’est constituée la théorie butlérienne ? Quelle est son influence sur les pratiques plasticiennes et sur les théories queer qui lui succèdent, participant indirectement (sinon involontairement) à la construction d'une esthétique drag qui intègre le transgenre ? En premier lieu, nous verrons que Butler étudie la performance drag à travers une anthropologie des artistes travestis élaborée par Esther Newton (Mother Camp, 1972), ainsi que par une critique du transgenre dans les films Paris is Burning (1991) et Boys don't cry (1999). Nous observerons ensuite comment les drag kings, photographiés par l’artiste Del LaGrace Volcano, sont interprétés par Judith Halberstam, à la suite de Butler, comme des performances qui dénaturalisent le genre et engagent parfois le corps des artistes jusqu'à la limite du transgenre. Enfin, à l’appui du philosophe Paul B. Preciado qui théorise sa propre "intoxication" à la testostérone (Testojunkie, 2008), nous aborderons l'art transgenre comme une esthétique biodrag qui incorpore littéralement la théorie butlérienne, en même temps qu'elle l'altère. À travers ces trois moments-clés, nous voudrions montrer comment la théorie butlérienne a produit une esthétique drag en mutation constante qui s'imprègne des grands récits de son temps, mais évolue aussi jusqu'à bouleverser les discours qui l'ont en partie engendrée / In Gender Trouble (1990), Judith Butler asserts that drag demonstrates the imitative structure of gender. If, in the common sense, the drag is often connected with cross-dressed performance, we will go to see with Butler that it recovers a complex set of bodily practices (sexual roles, body modifications, etc.). Then, how was etablished the Butler’s theory? What is its influence on the artistic practicals and on the queer theories that succeed her, contributing indirectly (if not involuntarily) to the construction of a drag aesthetic which integrates the transgender? Firstly, we will see that Butler studies the drag performance through an anthropology of the female impersonators elaborated by Esther Newton (Mother Camp, 1972) as well as by criticism of the transgender in the films Paris is Burning (1991) and Boys don't cry (1999). We observe afterwards how, after Butler, Judith Halberstam interprets the drag kings, photographed by the artist Del LaGrace Volcano, as performances whom denaturalize gender and, sometimes, engage the body of the artist until the limit of the transgender. At last, by using the philosophy of Paul B. Preciado who theorizes his own testosterone "intoxication" (Testojunkie, 2008), we will discuss the transgender art like a biodrag aesthetic which literally incorpore the Butler’s theory, at the same time that she modifies it. Through these three moments, we would want to show how Butler’s theory produced a drag aesthetics constantly changing which is permeated with grand narratives of his time, but also evolves until overturn the speeches which partially engendered it

The road transport industry is facing a strong need for fuel consumption reduction, driven by the necessity of decreasing polluting emissions, such as CO2 and NOX, as well as coping with strict regulations and increasing fuel costs. For road vehicles the aerodynamic drag constitutes a major source of energy consumption, and for this reason improving the aerodynamic performance of the vehicle is an established approach for reducing fuel consumption and greenhouse gases emissions. In this Thesis work, Computational Fluid Dynamics (CFD) investigations have been carried out in order to investigate and improve the aerodynamic performance of an unloaded timber truck. The work has been divided in two parts. In a first phase, a preliminary study was carried out on a simplified tractor-trailer model in order to establish a suitable computational grid and turbulence model. The hexcore-mesh showed a better performance over the tet- and poly-mesh types. Among the selected RANS turbulence models, the Realizable k − ε with Enhanced Wall Treatment (EWT) and y+ > 30 showed the highest reliability of results in comparison with experimental data and existing CFD investigations. In a second phase, the flow field around the baseline unloaded timber truck was analysed in order to highlight potential regions for drag reduction. The truck cabin-bulkhead gap, bunks, the exposed wheels and the stakes were found make key contribution to the drag build-up. The analysis confirmed the 5◦-yaw case to be the most representative for the wind-averaged drag coefficient. Geometry modifications were implemented in order to improve the aerodynamic performance in the selected areas, and subsequently combined into aero-kits in order to enhance the performance, analysed for the 5◦-yaw case. The combination of extended side skirts, bulkhead shield and collapsed stakes yielded a remarkable result of more than 30% decrease in the wind-averaged drag coefficient, achieved by reducing the flow separation on the cabin leeward A-pillar, and by shielding areas of high stagnation pressure from the side wind. Furthermore, a parallel study was conducted on the development of a procedure for the automatic post-processing of results. The outcome was a set of Python scripts to be used with Kitaware Paraview in order to automatically obtain figures of surface variables distributions, iso-surfaces, velocity profiles, drag build-up and total pressure contours. The procedure was finally extended to include the case comparison. / ETTaero2