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Performance when gliding in the streamlined position depends on a swimmer’s morphological characteristics, body orientation and water characteristics. The purpose of this thesis was twofold. First to identify and assess the effect of controllable factors that contribute to glide performance and second to form the foundations of an improved approach of simulating the fluid flow around the swimmers’ body. To address the purposes of the thesis four investigations were conducted. Study 1. The effect of the head position on glide performance was investigated. When the high, medium and low head positions were compared, it was found that swimmers experience significantly greater resistance and decelerate faster when they adopt a high head position. It was also found that there is no significant difference between the medium and low head position indicating for the first time that swimmers can choose any of the positions according to their natural tendency. Study 2. The second study examined the effect of gliding depth on gliding performance. A range of depths was investigated ranging from 0.8 m to 0.2 m from the water surface. The results demonstrated significantly higher glide factor values for glides at a greater depth when compared to glides closer to the water surface highlighting the retarding effect of wave drag when gliding close to the surface. The optimum gliding performance was reported for glides at 0.8 m from the surface. Study 3. The third study investigated the effect of full body swimsuits on glide performance. According to the findings, it is demonstrated for the first time that the improved gliding performance when wearing full body swimsuits is linked to changes in swimmers’ morphology due to compression. Study 4. In the fourth study the magnitude of resistive forces applied on a swimmer’s body when gliding underwater was assessed with the use of computational fluid dynamics (CFD) and the LES approach. The results showed a close match between the glide factor values of the experimental and the computational findings demonstrating the effectiveness of the CFD method when the LES approach is employed.

Superhydrophobic surfaces are able to entrap gas pockets in-between surface roughness elements when submerged in water. These entrapped gas pockets give these surfaces the potential to reduce drag due to the overlying flow being able to locally slip over the gas pockets, resulting in a mean slip at the surface. This thesis investigates the different effects that slip and the texturing of the surface have on turbulence over superhydrophobic surfaces. It is shown that, after filtering out the texture-induced flow, the background, overlying turbulence experiences the surface as a homogeneous slip boundary condition. For texture sizes, expressed in wall units, up to $L^+ \lesssim 20$ the only effect of the surface texture on the overlying flow is through this surface slip. The direct effect of slip does not modify the dynamics of the overlying turbulence, which remains canonical and smooth-wall-like. In these cases the flow is governed by the difference between two virtual origins, the virtual origin of the mean flow and the virtual origin experienced by the overlying turbulence. Streamwise slip deepens the virtual origin of the mean flow, while spanwise slip acts to deepen the virtual origin perceived by the overlying turbulence. The drag reduction is then proportional to the difference between the two virtual origins, reminiscent of drag reduction using riblets. The validity of slip-length models to represent textured superhydrophobic surfaces can resultantly be extended up to $L^+ \lesssim 20$. However, for $L^+ \gtrsim 25$ a non-linear interaction with the texture-coherent flow alters the dynamics of the background turbulence, with a reduction in coherence of large streamwise lengthscales. This non-linear interaction causes an increase in Reynolds stress up to $y^+ \lesssim 25$, and decreases the obtained drag reduction compared to that predicted from homogeneous slip-length models.

While tracking balloons for wind characterization, there was a question about the theoretical rise rate and corresponding coefficient of drag of a balloon shape as compared to a sphere. Since there are many studies published detailing the drag on spherical shapes, the question of whether or not a balloon can be treated as a sphere begged to be answered. In this study we apply Computational Fluid Dynamic (CFD) modeling to compare the aerodynamic behavior and drag of a sphere to that of a balloon as it moves through fluid at Reynolds numbers from 10,000 to 100,000. Fluent CFD models are created and used to estimate the coefficient of drag (Cd) vs. Reynolds number (Re) for a sphere and for a balloon shape. Details are given for the meshed model creation and the simulation methods. Sphere model results are compared to data provided in published literature. Sphere and balloon model results are compared to each other. The results of this study show that the drag on a balloon is not statistically different from a sphere. While there are differences in the flow characteristics over the two shapes, a spherical shape is a good approximation for a balloon shape.

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Condragulations, fierce, realness, werk or «Shante, you stay» are only some of the expressions from the contestants’ lexicon of RuPaul’s Drag Race (RPDR), a popular reality television show that started airing in 2009 in the USA. Through an academic lens, the study of this type of expression was anecdotally called “lavender linguistics,” during the first explorations of the sexual minorities’ ways of talking. Since then and till now, concepts related to gender, sexuality, and the works of representation have influenced both linguistics and Translation Studies, which in turn has led to critical perspectives on translation, identity transfer, acculturation and, of course, the way language works. This paper begins by briefly referring to drag queens living in Lima, Peru, and how they have changed the way they talk to each other and about themselves. As will be argued, a cultural product such as RPDR and the necessary interlingual subtitling into Spanish –commercial or fan-made– have been influencing their linguistic engagement. Further on, the concepts of camp and camp talk will be presented as they were first introduced to Translation Studies with the work of Keith Harvey during the late 1990’s. Camp representations will be then analyzed in commercial and fan-made subtitles to reveal the semiotic and pragmatic constraints resulting from cultural-specific gay identities. From this first approach, new inquiries on audiovisual translations in general and identity acculturation in particular will be proposed. / Revisión por pares

Fuel represents a major proportion of road transport expenditure and it is likely that this proportion will increase. At typical road speeds approximately half of the total fuel used is consumed in overcoming aerodynamic drag, hence the determination and reduction of aerodynamic drag is of considerable importance. This is normally performed by scale testing in wind tunnels with relatively smooth flow. When modelling an atmospheric crosswind in the tunnel the relative air direction is generated by yawing the model at an angle to the oncoming flow. This procedure does not reproduce the inherent turbulence in atmospheric winds. A review of the literature showed a poor correlation between road and wind-tunnel results often attributed to the lack of tunnel turbulence. The work presented herein involves road and wind-tunnel tests to investigate these discrepancies and aims to improve the accuracy of wind-tunnel modelling for commercial vehicles. Wind-tunnel and on-road tests which determine drag coefficient reductions from aerodynamic devices fitted to commercial vehicles are described. Two series of road tests utilised pairs of commercial vehicles: International Harvester Australia low-forward-entry articulated vehicles with maximum road-legal size containers and Isuzu rigid (box-van) vehicles fitted with cuboid containers. Drag coefficient reductions were calculated from fuel meter readings in the trucks and measurements of yaw angle and relative velocity from an instrumented chase car. Tunnel testing was performed on scale vehicles in the Royal Melbourne Institute of Technology (RMIT) Industrial Wind Tunnel in relatively smooth flow (longitudinal intensity = 1.7%). Large differences between road and tunnel drag coefficients at high yaw angles were found. The on-road turbulent wind environment was measured utilising a vehcle instrumented with mast-mounted cross-wire and propeller-vane anemometers. Atmospheric mean wind speeds of 1 m/s to 9 m/s, aligned at various angles to .the road direction, were encountered and data were taken with the vehicle stationary and moving at 27.8 m/s (100 km/h). Longitudinal and lateral intensities and spectra were calculated thus providing new information on the wind environment for vehicles. A mathematical model of the turbulence intensities perceived by a moving vehicle was developed. This utilised atmospheric wind data obtained whilst the vehicle was stationary to predict moving vehicle data. Measured and predicted intensities for the moving vehicle were in good agreement for roads with no local roadside obstructions (eg. trees) thus validating the model, but the obstructions increased data scatter and augmented the lateral intensities by typically 30%) with little change in the longitudinal intensities. Peaks in the longitudinal and lateral spectra for the moving vehicle were at approximately 1.0 Hz and most of the energy was contained between 0.1 Hz and 10 Hz. Subsequent tunnel tests were performed using five levels of grid-generated turbulence and the mathematical model was used to predict the on-road data from tunnel tests. Better agreement was found at high yaw angles when the correct longitudinal intensities were used. However the scales of turbulence in the tunnel were too short for correct modelling. Flow visualisation studies over the model and full-size cab roofs indicated differences in flow patterns that were attributed to Reynolds number differences. The mathematical model and measurements described in this thesis showed that high yaw giigles are always accompanied by relatively high turbulence intensities and it was concluded that the modelling of turbulence characteristics for commercial vehicles is more important than other modelling parameters such as a moving ground. Most major vehicle aerodynamics tunnels have very low turbulence levels (longitudinal rms intensities commonly less than 0.5%) whereas measured on-road values of 2% to 5% are typical (with higher values of lateral intensities). It is therefore recommended that for vehicle aerodynamic generally more attention be paid to correctly modelling the intensities and scales of turbulence in wind tunnels and understanding the effects of typical turbulence characteristics on vehicle drag.

<p>The drag approximations done in the initial design phase needed to be verified. A model of the aircraft has been analyzed with CFD and results examined to see how accurate the estimations were. A step by step analysis was made and then a simulation was run. The drag results of the CFD analysis did not meet the goal of the initial design study. Several reasons for this are discussed. The analysis shows that the aircraft design works well aerodynamically but also shows a few areas where the design can be improved.</p> / <p>Det approximerade värdet på luftmotståndet som gjordes I den preliminära designfasen behövde verifieras. En flygplansmodell har analyserats med CFD och resultaten har undersökts för att se hur exakta antagandena var. En analys gjordes steg för steg och slutligen har en simulering utförts. Det uppmätta luftmotståndet motsvarade inte målet i den preliminära designfasen. Flera olika anledningar till detta diskuteras. Analysen visar att denna flygplansdesign fungerar bra aerodynamiskt men identifierar också en del punkter på vilken den kan förbättras.</p>

<p>Att kommunicera och utifrån det ta initiativ och utföra en handling är för många barn svårt.  Tillkommer det dessutom en funktionsnedsättning försvårar det oftast situationen. Förmågan till samspel, initiativ och handling kan då behöva medvetandesgöras med hjälp av olika medel.</p><p>Syftet med detta examensarbete är att beskriva FMT-metoden, samt att nå en djupare kunskap kring ämnet autism. I mitt arbete har jag valt att med FMT-metoden (Funktionsinriktad musikterapi) förmedla och beskriva hur man kan nå samverkan med barn med autism och autismliknande drag.</p><p>Litteraturstudie har genomförts i ämnena musikterapi, FMT-metoden, autism och autismliknande drag samt utvecklingsstörning. En sammanfattning har gjorts av dokumenterad information, i form av videoinspelningar och fallbeskrivningar av två barn som jag följt under utbildningens gång.</p><p>I min slutsats kom jag fram till att jag observerat en stor utveckling hos barnen vad gäller förmågan till samverkan, initiativtagande och utförandet av en egen bestämd handling med FMT-metoden som medel.</p>