Orientador: Orival Andries Júnior / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Educação Física / Made available in DSpace on 2018-08-16T18:10:16Z (GMT). No. of bitstreams: 1 Barbosa_AugustoCarvalho_D.pdf: 7576445 bytes, checksum: 04d87ab5c33f1dc5ca635490134e7f67 (MD5) Previous issue date: 2010 / Resumo: O objetivo do presente estudo foi analisar as respostas agudas de parâmetros biomecânicos à utilização de diferentes tamanhos de palmar no nado crawl. Foram selecionados 14 nadadores homens (idade: 20.0 ± 3.7 anos, altura: 1.84 ± 0.08 m, massa corporal: 76.3 ± 8.6 kg, melhor tempo nos 100 m livre: 53.70 ± 0.87 s) competitivos em nível nacional. Para avaliação da força propulsora foram realizados 02 esforços máximos de 10 s no nado completamente atado. Em cada um foram analisadas 08 braçadas consecutivas, de onde se extraiu os valores médios de força pico (Fpico), força média (Fméd), taxa de desenvolvimento de força (TDF), impulso (ImpF), duração da braçada (DUR), tempo para atingir a força pico (TFpico) e força mínima (Fmín). Os nadadores também realizaram 02 esforços máximos na distância de 25m para obtenção da velocidade média em 15m (VM15m) (foram desprezados os 07 primeiros e 03 últimos metros), da frequência (FB15m) e do comprimento de braçadas (CB15m). Ambos os protocolos foram repetidos em 05 situações, a saber: livre de material (LVR), com palmar pequeno (PP, 280 cm²), médio (PM, 352 cm²), grande (PG, 462 cm²) e extragrande (PGG, 552 cm²). A ANOVA one way e o teste de Kruskal-Wallis foram adotados para comparar as situações. Quando detectado um efeito significante, recorreu-se ao teste de post-hoc de Scheffé (dados paramétricos) ou ao teste de Mann-Whitney com ajuste de Bonferroni (dados não-paramétricos) para localização das diferenças. Foi adotado um nível de significância de 5%. O aumento artificial da área da mão possibilitou o deslocamento de uma maior massa de água ocasionando um incremento significante na Fpico nas comparações LVR x PG, LVR x PGG e PP x PGG. Com isso, houve uma diminuição da velocidade da mão, que repercutiu em um aumento da DUR nessas mesmas comparações. Fméd e/ou TDF não apresentaram modificações significantes devido às alterações concomitantes das variáveis cinéticas e temporais que as influenciam. Esse resultado da TDF, aliado ao aumento do ImpF (principal variável associada à velocidade) nas comparações LVR x PG, LVR x PGG e PP x PGG, pode indicar que PG e PGG propiciam o desenvolvimento da propulsão sem ocasionar prejuízos aparentes na capacidade explosiva dos nadadores. O TFpico aumentou de LVR para PGG e PP para PGG devido ao aumento da Fpico e da diminuição da Fmín. A Fmín diminuiu significantemente apenas de LVR para PGG, apontando para uma possível alteração da relação entre o início e término da propulsão de ambos os braços. A ausência de alterações significantes na VM15m pode estar associada ao aumento do arrasto de onda. A FB15m diminuiu significantemente de LVR para PGG e de PP para PGG, enquanto o CB15m apresentou um comportamento exatamente inverso nas mesmas comparações. Conclui-se que, de forma aguda, o tamanho do palmar influencia principalmente a magnitude da força propulsora gerada e o seu comportamento ao longo do tempo / Abstract: The aim of this study was to analyze the acute responses of biomechanical parameters to different sizes of paddles in front-crawl stroke. Fourteen national competitive male swimmers (Age: 20.0 ± 3.7 years, height: 1.84 ± 0.08 m, body mass: 76.3 ± 8.6 kg, 100- m best time: 53.70 ± 0.87 s) volunteered for this investigation. For the propulsive force evaluation, 02 maximum efforts of 10 s were accomplished in the fully tethered swimming. In each effort, 08 consecutive strokes were analyzed to extract the average value of peak force (Fpeak), mean force (Fmean), explosive force (TDF), impulse (ImpF), stroke duration (DUR), time to peak force (TFpeak) and minimum force (Fmin). Additionally, swimmers accomplished two 25-m maximal swimming in order to measure the average velocity in 15 m (VM15m) (first 07 and last 03m were discarded), the stroke rate (SR15m) and the stroke length (SL15m). Both testing protocols were repeated in 05 conditions: conventional swimming (LVR), wearing small (PP, 280 cm²), medium (PM, 352 cm²), large (PG, 462 cm²) and extra-large paddles (PGG, 552 cm²). The one way ANOVA or the Kruskal-Wallis test were adopted for intersituations comparisons. Possible significant differences were detected by Scheffé post-hoc test (for parametric data) or Mann-Whitney test with Bonferroni adjustment (for non-parametric data). The significance level was set at 5%. The artificial enlargement of the hands allowed the swimmers to push off against a bigger mass of water and provided a significant increase of the Fpeak in the comparisons LVR x PG, LVR x PGG and PP x PGG. Because of this, there was also a hand's velocity reduction, which repercuted in a greater DUR in these same comparisons. The Fmean and/or the TDF did not change significantly due to the concomitant modifications of the kinetic and temporal variables that influence them. This result of the TDF, associated to the increase of the ImpF (the main variable related to swimming velocity) in the comparisons LVR x PG, LVR x PGG and PP x PGG, might indicate that PG and PGG propitiate the development of propulsion without any apparent damage in the swimmer's explosiveness. The TFpeak increased from LVR to PGG and from PP to PGG due to the increase of the Fpeak and the decrease of Fmin. The Fmin decrease significantly only from LVR to PGG, pointing to a possible modification in the relation between the beginning and the end of propulsion of both arms. The absence of significant changes in the VM15m might be related to the wave drag increase. The SR15m decrease significantly from LVR to PGG, while the SL15m presented exactly the inverse behavior. It can be concluded that, acutely, the different sizes of hand paddles influence mainly the magnitude of the propulsive force generated and its behavior throughout the time / Doutorado / Ciencia do Desporto / Doutor em Educação Física

Due to a trend towards Ultra High Bypass Ratio engines the corresponding engine/airframe interference is becoming a key aspect in aircraft design. The present economic situation increases the pressure on commercial aviation companies to reduce the Direct Operating Cost, and the environmental situation requires a new generation of aircraft with a lower environmental impact. Therefore detailed aerodynamic investigations are required to evaluate the real benefits of new technologies. The presented research activity is part of a long-term project with the main objective of generating a reliable and accurate tool to predict the performance of an aircraft over the whole flight domain. In particular the aim of this research was to perform advanced CFD in order to establish a tool able to evaluate engine installation effects for different configurations and attitudes. The developed tool can be provided with correlations of the Net Propulsive Force (NPF), the force exerted by the power-plant to the aircraft, as a function of position. This can be done in principle at cruise, hold, climb, descent, take-off and landing, to model the different integration effects at different phases. Due to the complexity of the problem it was only possible at an initial stage to determine these correlations at cruise condition. Two parametric test cases were evaluated, showing that the engine horizontal positioning can influence the mission fuel burn by up to 6.4%. According to the extensive literature review that has been done, this study can be regarded as the first open literature engine position-NPF parametric study using CFD. Even though no correlations were extracted for other conditions; a deployed high-lift wing configuration was also studied in detail, defining the main aerodynamics effects of the engine integration at high angle of attack. A topological study of the high-lift installation vortices is presented in this work and it can be considered the first in the open literature. It should be pointed out that extensive research is currently underway to correctly evaluate the high-lift aerodynamic using CFD. The Propulsive System Integration (PSI) in high-lift conditions is adding flow features to an already demanding problem, making it a real challenge for the numerical methods. Nevertheless the additional effects of a nacelle chine on the maximum lift were also evaluated. The main outcomes of this PhD research were: a coupled performance modelling tool able to handle the effects of engine-airframe integration as a function of geometry and attitude, and a topological study of the high-lift installation vortices. During the course of the work, this research was successfully suggested as an extra activity for the European NEWAC project (New Aero Engine Core Concepts), and resulted in a new deliverable for that project.

Due to a trend towards Ultra High Bypass Ratio engines the corresponding engine/airframe interference is becoming a key aspect in aircraft design. The present economic situation increases the pressure on commercial aviation companies to reduce the Direct Operating Cost, and the environmental situation requires a new generation of aircraft with a lower environmental impact. Therefore detailed aerodynamic investigations are required to evaluate the real benefits of new technologies. The presented research activity is part of a long-term project with the main objective of generating a reliable and accurate tool to predict the performance of an aircraft over the whole flight domain. In particular the aim of this research was to perform advanced CFD in order to establish a tool able to evaluate engine installation effects for different configurations and attitudes. The developed tool can be provided with correlations of the Net Propulsive Force (NPF), the force exerted by the power-plant to the aircraft, as a function of position. This can be done in principle at cruise, hold, climb, descent, take-off and landing, to model the different integration effects at different phases. Due to the complexity of the problem it was only possible at an initial stage to determine these correlations at cruise condition. Two parametric test cases were evaluated, showing that the engine horizontal positioning can influence the mission fuel burn by up to 6.4%. According to the extensive literature review that has been done, this study can be regarded as the first open literature engine position-NPF parametric study using CFD. Even though no correlations were extracted for other conditions; a deployed high-lift wing configuration was also studied in detail, defining the main aerodynamics effects of the engine integration at high angle of attack. A topological study of the high-lift installation vortices is presented in this work and it can be considered the first in the open literature. It should be pointed out that extensive research is currently underway to correctly evaluate the high-lift aerodynamic using CFD. The Propulsive System Integration (PSI) in high-lift conditions is adding flow features to an already demanding problem, making it a real challenge for the numerical methods. Nevertheless the additional effects of a nacelle chine on the maximum lift were also evaluated. The main outcomes of this PhD research were: a coupled performance modelling tool able to handle the effects of engine-airframe integration as a function of geometry and attitude, and a topological study of the high-lift installation vortices. During the course of the work, this research was successfully suggested as an extra activity for the European NEWAC project (New Aero Engine Core Concepts), and resulted in a new deliverable for that project.

Wireless applications have become a common part of daily life. Whether it is mobile phones, the Wi-Fi router at home, the keycard which has replaced the car key, a radio frequency identification access system to a building or a Bluetooth headset for your computer or phone, the means of modern wireless data exchange is an omnipresent technology. In sports, the market is in its infancy for wireless, technical applications or gadgets. Only heart rate monitors and GPS watches are currently used by recreational athletes. Even though most of the larger sports equipment companies regularly launch new products related to sports performance monitoring and mobile phone technology, product innovation leaps are rare.In this work the design of a wireless sports performance measurement platform is presented. Using the example of kayaking, this platform is configured as a paddle performance measuring system, the Kayak XL System, which can monitor propulsive paddle force, paddle kinematics and boat velocity, interalia. A common mobile phone platform has been chosen as the user interface for this system. The design approach focussing on user requests, demands and expectations in combination with the process of iterative technical development are unveiled in this thesis. An evaluation of the system is presented and the work is finalised with an overview of further systems which have been designed based on the developed measurement platform. The Kayak XL System is a flexible system designed to be mounted onto any standard kayak paddle and installed in any competition kayak. Versatility, unobtrusiveness and usability were major design concerns. The developed system consists of four modules plus a software which has been designed for Android mobile phones. The phone communicates with each of the four modules trough Bluetooth radio. These four modules are also referred to as nodes and have specific measurement purposes. Two nodes have been designed to measure paddle force and kinematics, one node has the purpose to measure foot stretcher force and boat motion data, and the fourth node enables a more convenient method of calibrating paddle force measurement. The fourth node is therefore only needed prior to performance data acquisition. Results show that paddle and foot stretcher force can be measured with a resolution below 1N after calibration. Installing the paddle nodes on a previously configured paddle without repeated calibration is facilitated with the compromise of a doubled error margin. The default sampling frequency is set to 100 Hz and can, like all system parameters, be configured on the mobile phone. Real-time computation of complex performance parameters is only limited by the phone CPU. The system adds twice 109 g to the paddle and approximately 850 g to the kayak, excluding the mass of the mobile phone / <p>QC 20120827</p>

Le crawl est actuellement la nage utilisée lors des épreuves de nage libre durant les compétitions de natation aux différentes allures de nage (sprint, demi-fond et fond). Les bras sont les segments corporels qui participent le plus à la propulsion. Les accélérations de ces segments, dans le milieu fluide au repos, génèrent un écoulement complexe qui est à l'origine des forces hydrodynamiques propulsives. L'analyse de cet écoulement est nécessaire pour en comprendre les principaux mécanismes. Dans ce cadre, des « paramètres cinématiques d'écoulement » (vitesse, accélération et orientation de la main, angles d'attaque et de sweepback) ont été définis afin d'analyser et comparer les différentes organisations gestuelles des nageurs et de leurs effets sur la propulsion. Deux des principaux axes d'investigation étaient de vérifier si ces paramètres variaient en fonction de l'allure, et aussi de déterminer quels paramètres cinématiques étaient les plus prépondérants dans la génération des mécanismes propulsifs. Pour cela, un système opto-électronique d'analyse cinématique, a permis de mesurer ces paramètres sur 17 nageurs experts. Par ailleurs, l'écoulement généré par le trajet des bras aux différentes allures a été simulé par résolution numérique instationnaire des équations de Navier-Stokes. Enfin, des mesures expérimentales d'effort ont été faites en nage attachée afin de connaître les forces propulsives.Il apparaît que l'augmentation de l'allure de nage peut davantage s'expliquer par la diminution des durées des phases non propulsives (entrée et allongement) plutôt que par l'augmentation des forces durant les phases les plus propulsives (balayages interne et externe). / Front crawl is a swimming stroke used at swimming competitions at freestyle different paces (sprint, middle distance and long distance). Propulsion in this stroke is achieved primarily by the forearm and hand. Accelerations of these segments, in a fluid at rest, generate complex flow that causes propulsive hydrodynamic forces. Analysis of this flow is necessary to understand the main mechanisms of propulsion. In this context, the "kinematic flow parameters" (velocity, acceleration and orientation of the hand, angles of attack and sweepback) have been defined to analyze and compare the different arm motions and their effects on propulsion. Two of the main axes of this investigation were to determine whether these parameters vary depending on the pace, and also to determine what kinematic parameters were most prominent in the generation of propulsive mechanisms. To this end, an optoelectronic system of motion capture was used to measure these parameters on 17 expert swimmers in free swimming. Furthermore, the flow generated by the experimentally acquired arm trajectory, at different swimming paces, was simulated by an unsteady numerical solution of the Navier-Stokes equations. Finally, tethered swimming experiments were carried out to measure the propulsive forces.The increase in forward velocity by increasing swimming pace can be explained by lower durations of non propulsive phases (entry and stretch) rather than by the generation of higher forces during the most propulsive phases (insweep and upsweep).