Aero Science

In the two decades since the first Felt frame was custom-built for an elite triathlete, the science of cycling aerodynamics has evolved significantly. Back then it wasn’t much of a science at all—it was more of an art, as craftsmen like Felt Bicycles namesake Jim Felt evolved the technology slowly and painstakingly over time.
How far we’ve come. Today, the engineers behind Felt’s innovative road, TT and triathlon bikes—including the all-new Felt DA—use highly advanced computer hardware and software to develop carbon fiber wonder bikes that can slice through the wind faster than anyone ever thought possible.
Some of the methods Felt currently uses to optimize aerodynamic efficiency include 3D modeling software, wind-tunnel testing and, of course, feedback from the world’s best athletes including three-time World Champion track racer Sarah Hammer.
Perhaps the most important tool Felt now employs when developing aerodynamic bikes is one that’s fairly new in the bicycle industry. It’s a mathematical modeling process called Computational Fluid Dynamics, or CFD. Commonly used in the design of F1 racecars and multi-million dollar yachts, CFD also helps Felt engineers analyze the complex aerodynamic flows that create drag on the rider and bike. The process allows Felt designers to develop solutions that give pro racers—and you—every possible advantage in the race against the clock.
So how does it work? Simply stated, CFD allows Felt engineers to predict the way different frame shapes and designs will perform in real-world wind conditions. It’s basically an analysis program that uses numbers and algorithms to measure airflow over the frame’s surface shapes as they are developed in CAD.
More accurate CFD simulations require more powerful computers and software, which is why Felt has partnered with one of the leaders in this field, a company called CD-adapco. With more than 30 years’ experience delivering industrial strength engineering simulations to a wide range of clients in the aerospace, automotive and marine industries, CD-adapco is a powerful partner in Felt’s efforts to build faster bikes. 

CD-adapco’s products allow Felt engineers to crunch massive amounts of data in as short a time as possible. This CFD analysis is really Step 1 of Felt’s development process. To understand just how big a role it plays, consider this statement from Felt engineer Ty Buckenberger: “The CFD analysis is an invaluable tool in evaluating and designing our tt/tri and aero road bikes.”

Of course, the DA represents a huge step forward in the effort to shave seconds off the clock.

Bill Clark, CD-adapco’s Senior VP of Sales and Support, said Felt’s use of this technology represents a real breakthrough. “Just a few years ago, Felt’s use of simulation would have been unthinkable because serious aerodynamic simulation was the sole preserve of the aerospace community, race car manufacturers and large automobile OEMs, each of whom employ large teams of dedicated specialists working around the clock to churn out engineering data capable of positively influencing the vehicle design,” said Clark.

To help model the DA, Felt engineers used a supercomputer called BoxCluster. The BoxCluster is basically the Bugatti Veyron of computers. With 16 processors in one screaming-fast box, it’s capable of working through more than 100 billion calculations per second to help guide Felt’s pursuit of aerodynamic perfection.

“Felt’s simulation-driven design process is a clear endorsement of CD-adapco’s central philosophy of increased innovation and reduced cost,” added Clark. “They use CFD to explore their designs and to reduce the amount of expensive physical testing.”

Indeed, with CD-adapco’s support, Felt can build a faster bike by eliminating guesswork and speeding up the development phase. “Basically, it’s like having a wind-tunnel inside a computer,” says Lane. “Faster computers allow quicker CFD analysis, so we can test many variables—different aerofoil sections, alternate tube shapes, interactions between the rider, frame and wheels—and we can either isolate them or analyze combined sections of the bike.”

Of course physical wind-tunnel testing and rider feedback are still vitally important to the process, but those two steps take time. By the time Felt’s pro racers get their hands on Felt’s latest means of gaining seconds on the competition, they’re racing with the confidence that comes from having the most advanced aerodynamics technology in the industry.