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The Effect of Depth on Drag During the Streamlined Glide: A Three-Dimensional CFD Analysis
Maria L Novais1, António J Silva, Vishveshwar R Mantha
1University of Trás-os-Montes and Alto Douro. Department of Sports, Health and Exercise, UTAD, Vila Real. Portugal. ; Research Centre in Sports, Health and Human Development, CIDESD, Portugal.
Journal of Human Kinetics
|March 15, 2013
Summary
Computational Fluid Dynamics (CFD) analysis revealed that deeper water reduces hydrodynamic drag for streamlined swimming glides. Maximum drag reduction occurs up to 0.75 meters, with minimal further benefit at greater depths.
Area of Science:
- Sports Science
- Fluid Dynamics
- Biomechanics
Background:
- Understanding hydrodynamic forces is crucial for optimizing swimming performance.
- The streamlined glide phase significantly impacts overall race time.
- Previous research has explored various factors affecting drag, but depth effects require further investigation.
Purpose of the Study:
- To analyze the impact of water depth on hydrodynamic drag during a streamlined glide in swimming.
- To determine the optimal depth for minimizing drag in the underwater glide phase.
Main Methods:
- Utilized Computational Fluid Dynamics (CFD) with a three-dimensional mesh and the K-epsilon turbulent model.
- Simulated flow around a 3D model of an Olympic swimmer in a streamlined prone position.
- Calculated drag force and coefficient at velocities from 1.5 to 2.5 m/s and depths from 0 to 1.0 m.
Main Results:
- Hydrodynamic drag decreased as water depth increased.
- Significant drag reduction was observed up to a depth of 0.75 meters.
- Beyond 0.75 meters, drag values remained relatively constant, indicating diminishing returns.
Conclusions:
- Water depth positively influences hydrodynamic drag reduction during the streamlined glide.
- Gliding deeper than 0.75 meters offers minimal additional benefit for reducing drag.
- Swimmers may not benefit from performing underwater glides beyond 0.75 meters depth.
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