Computational Fluid Dynamics

CFD s-cidesd cor

The goals, in the framework of the project

The current research team has studied the forces generated by the swimmer’s propelling segments and the magnitude of drag forces resisting forward motion, using this computational tool. CFD methodology allows to computationally understanding the water flow around the swimmer and to analyses the produced propulsive and resistive forces. The previous works have been done on top level swimmers in order to understand and improve their performance. The present research project is an upload extension of the works that have been developed by this research team, to complete the data in swimming and also to apply the CFD methodology into other kind of subjects (people with disabilities) and other aquatic sports, with possible applications to improve sport equipment. Concerning swimming research, we intend to get involved in the scope of sport for disabilities, analysing the forces produced by the swimmers with physical disabilities, namely, the Paralympic swimmers. The application of CFD in this field is recent, but the vast applicability and importance of these studies have been demonstrated.

Screen Shot 2013-07-17 at 2.42.32 PM

Methodologies and approaches proposed to reach the goals

Computational fluid dynamics (CFD) methodology is one of the several methods that have been applied in sports research to observe and understand water flow situations around the human body and its application to improve swimming technique, equipment and performance. Therefore, the use of CFD can be considered as a new step forward to the understanding of swimming mechanisms and seems to be an interesting approach to apply in aquatic activities research. In aquatics sports, although CFD has been mainly applied in swimming, we aim to use the knowledge gathered from the swimming studies to enlarge the application of this numerical tool to other aquatic activities, such as sailing, windsurfing, surfing, canoeing, kayaking and rowing. CFD analysis in swimming has addressed to understand two main topics of interest: the propulsive force generated by the propelling segments and the drag forces resisting forward motion, since the interaction between both forces will influence the swimmer’s speed. However, the majority of the studies have been conducted under steady flow conditions, assuming that the direction and velocity of the propelling segments and the swimmer displacement do not change over time. Moreover, the swimmer is generally modelled under the water, considering no interaction between the air and water during swimming. Thus, the propulsive basis in swimming will be evaluated taking into account these two important gaps. The unsteady flow is a main characteristic of the swimming movement.
The change in the direction and velocity of the propelling segments will be considered using programming techniques, “moving meshes” and user defined functions in the numerical simulations. Thus, allowing simulating the relative movement of the propelling segments and the body-roll, pitch and heave. In addition, including the air flow inside the computational domain can play an important role to increase the strength of the CFD methodology in swimming research. The approximation of CFD studies into the real situation seems to be the key point of this project, trying to introduce new insights in the designing of advanced propulsive techniques in swimming; new ways of streamlining the body during the displacement; or even the development of new materials (suits and others) helping the swimmer moving fast. With CFD methodology it is possible to analyse the velocity and the direction of the water flow around the body, thus allowing evaluating the different paths due to different suit tissues and body compressive effects. However, the major research conducted in this field is performed with great secrets. Concerning swimming, we intend to enlarge this approach into the scope of sport for people with disability, analysing for instance the forces produced by swimmers with physical disabilities, as the Paralympic swimmers. The sport for people with disabilities is becoming more and more popular. Although the scientific community has conducted efforts to analyses the handicapped athletes, we believe there is a lot to do to decrease the gap between the research conducted with able bodied people and people with disabilities. With CFD it is possible to numerically test models of people with different physical disabilities, as swimmers with limb amputations, allowing evaluating asymmetric forces produced by the handicapped swimmers. These analyses will permit to prescribe training programs to improve performance and prevent injuries, thus improving the physical grounding of these athletes. Portugal has a large tradition in these sports, namely obtaining very good results in the Paralympic Games in swimming. Therefore, the study of our athletes and the prescription of some technical concerns seem to be very gratifying for our team.

Screen Shot 2013-07-17 at 2.44.00 PM

The expected results for this group.

In addition to several master and doctoral thesis, the main goals from the produced papers are within the aquatics hydrodynamics scope, by applying CFD in sport aquatic activities, spreading the use of this recent technique (in sports context), designing new propulsive techniques and new ways of streamlining the body in swimming. Additionally, there will be a focus on the development of new materials (suits, and others), and to extend CFD to other aquatic activities, such as canoeing, rowing and sailing.

boletim 2

Connections with other groups

CFD is a project that gathers goals from the Sports Performance Group. It has formal participation of the Sport Faculty of Porto, the Polytechnic Institute of Bragança, the Norwegian School of Sport Sciences, the University of Savoie, the University of Beira Interior and the Research Center of Agro-Ambiental and Biological Technology (FCT accredited).

The role of each partner and institution in the task

CFD formal modelling and simulations is done by researchers from both CIDESD and the Research Center of Agro-Ambiental and Biological Technology. The data gathering process will be carried by researchers from CIDESD and from the Polytechnic Institute of Bragança, the Norwegian School of Sport Sciences, the University of Savoie and the University of Beira Interior.