In light of the recent, thrilling accomplishments of the U.S. men’s Olympic swim team, I thought it proper to focus on just how much physics goes into every aspect of Olympic swimming- from training and pool design right down to those tiny swim suits.
In ultra competitive swimming, flow is everything. Understanding how a swimmers movements or force impacts the water as his or her body gracefully glides and pushes is key to understanding how motion affects flow. Here is where fluid mechanics comes in: to help swimmers measure the flow and force generated in a natural, seemingly unpredictable environment.
This year the U.S. team is equipped with the technology needed to “know the flow”, thanks to a fluid mechanics professor at Rensselaer Polytechnic Institute in Troy, N.Y. Timothy Wei invented a new flow measurement tool designed to help swimmers move faster and more effectively, knocking off seconds from their lap times.
Using technology originally designed for aerospace research, the system works by taking actual flow measurements of the swimmers, in real-time with a video-based flow measurement technique known as Digital Particle Image Velocimetry (DPIV). It can identify important vortices, pinpoint the movement of the water, and determine how much energy the swimmer exerts.
Onto the Pool. The mammoth of a swimming pool in Beijing is more than than a giant concrete hole filled with water and chemicals. This pool’s got speed. That is, it’s specifically designed to make swimmers move faster. The Beijing pool is almost 10 feet deep; 3 feet deeper than previous Olympic-sized pools. Perfect water depth is essential to maximizing vision and orientation.
Water that is too deep can mess up vision and perception. However, its has to be deep enough to adequently dissipate waves and turbulence. The lane lines that divide the swimmers are designed with new technology that further dissipate turbulent water. The flatter the water remains, the better.
The pool is also wider than most, with 10 lanes instead of the old eight, and perforated gutters are installed on its side walls. This ensures that pesky waves created during the races don’t bounce back into the lanes and slow down the swimmers.
Finally, the swim suits themselves are newly designed to decrease surface friction and hydrodynamic drag. Speedo’s new LZR Racer worn by Phelps and others this year in Beijing is based on aerospace engineering principles that actually minimize muscle oscillations. The shark skin-like suit also stretches over more surface area, thereby compressing the swimmer’s body into a better hydrodynamic shape.