COMPUTATIONAL FLUID DYNAMICS: AN ANALYTICAL TOOL FOR THE 21ST CENTURY SWIMMING RESEARCH

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Publications

Physical activity level as a booster of entrepreneurial intention: a social innovation approach

Publication . Rodrigues, Ricardo; Marques, Carla; Esteves, Dulce; Brás, Rui; Santos, Gina; Gouveia, Ana; Duarte, Paulo; Pinheiro, Paulo; O'Hara, Kelly; Marques, Vanessa

This study aims to investigate if engaging in physical activity (PA) and gender influences people’s entrepreneurial intention (EI). A survey for measuring EI and PA was developed and administered to the general population. The data were collected with a questionnaire distributed across all continental Portuguese regions. A two-way analysis of variance was used to test the influence of PA level and gender in EI. The results highlight that PA and gender have an impact on EI. This study’s main practical implication is that evidence was found that people need to be involved in more PA, especially in high PA level, because the results show that there is an association with increased levels of EI. This paper contributes to filling a gap in the literature by identifying the importance of PA for the increase of EI. This relationship may be a consequence of skills promoted by the practice of PA and also the development of some personal psychological and cognitive characteristics such as autonomy, risk tolerance, and leadership. The main implication resulting from this study is that it is essential to develop and booster PA into society, namely through PA programmes in organisations, not only for improving persons’ health condition but also as a social benefit, that can promote social innovation and entrepreneurship.

2019Journal article

Open access

Analysis of wind velocity and release angle effects on discus throw using computational fluid dynamics

Publication . Rouboa, Abel I; Reis, Vitor M.; Mantha, Vishveshwar R.; Marinho, Daniel A.; Silva, António J.

The aim of this paper is to study the aerodynamics of discus throw. A comparison of numerical and experimental performance of discus throw with and without rotation was carried out using the analysis of lift and drag coefficients. Initial velocity corresponding to variation angle of around 35.5° was simulated. Boundary condition, on the top and bottom boundary edges of computational domain, was imposed in order to eliminate external influences on the discus; a wind resistance was calculated for the velocity values of 25 and 27 m/s. The results indicate that the flight distance (D) was strongly affected by the drag coefficient, the initial velocity, the release angle and the direction of wind velocity. It was observed that these variables change as a function of discus rotation. In this study, results indicate a good agreement of D between experimental values and numerical results.

2013Journal article

Open access

Analysis of drafting effects in swimming using computational fluid dynamics

Publication . Silva, António; Rouboa, Abel I; Moreira, António; Reis, VM; Alves, Francisco; Vilas Boas, J. Paulo; Marinho, Daniel

The purpose of this study was to determine the effect of drafting distance on the drag coefficient in swimming. A k-epsilon turbulent model was implemented in the commercial code Fluent(®) and applied to the fluid flow around two swimmers in a drafting situation. Numerical simulations were conducted for various distances between swimmers (0.5-8.0 m) and swimming velocities (1.6-2.0 m.s(-1)). Drag coefficient (Cd) was computed for each one of the distances and velocities. We found that the drag coefficient of the leading swimmer decreased as the flow velocity increased. The relative drag coefficient of the back swimmer was lower (about 56% of the leading swimmer) for the smallest inter-swimmer distance (0.5 m). This value increased progressively until the distance between swimmers reached 6.0 m, where the relative drag coefficient of the back swimmer was about 84% of the leading swimmer. The results indicated that the Cd of the back swimmer was equal to that of the leading swimmer at distances ranging from 6.45 to 8. 90 m. We conclude that these distances allow the swimmers to be in the same hydrodynamic conditions during training and competitions. Key pointsThe drag coefficient of the leading swimmer decreased as the flow velocity increased.The relative drag coefficient of the back swimmer was least (about 56% of the leading swimmer) for the smallest inter-swimmer distance (0.5 m).The drag coefficient values of both swimmers in drafting were equal to distances ranging between 6.45 m and 8.90 m, considering the different flow velocities.The numerical simulation techniques could be a good approach to enable the analysis of the fluid forces around objects in water, as it happens in swimming.

2008Journal article

Open access