A new piece in the esteemed journal Science breaks down the feat of engineering behind the magic of Kelly Slater's manufactured wave. In the article, "A surfer and a scientist teamed up to create the perfect wave," writer Jon Cohen discusses brainwork behind the experience that even got Gabriel Medina to get effusive.
It all started, of course, with Slater's dream of creating the perfect wave. Not the awkward imitation that a lot of surfers have tried, but the real deal -- and maybe even better. In 2006, when he set out to bring his dream to life, he tracked down Adam Fincham, a Jamaican-born USC researcher and expert in fluid mechanics. At the time, Fincham had no idea who Slater was. But with a body of work that, according to Science, includes papers on topics like digital particle imaging velocimetry for laser diagnostics, he had the type of expertise that would complement that of a single-minded surfer with 11 World Titles.
Surf fans know what came next --- well, 11 years later. There were those early unveilings, with sessions from Stephanie Gilmore and other lucky ducks; September's Future Classic test session; and the slow trickle of clips from pro after pro -- Gerry Lopez on the left, Shane Dorian on the right, little Jackson Dorian getting shacked -- giving the wave their gushy, awestruck blessings. But behind the scenes, the road to perfection was a little less barrels-for-days and a little more let's-work-in-anonymity-for-a-decade-and-see-what-happens.
According to the article, one of the biggest hurdles to achieving the magic of Slater's wave was the sheer scale, and the physics of what happens to water at that scale. Per Cohen, the journalist, "Tanks in labs typically make waves a few centimeters tall, which can be modeled with linear equations: What you put in reliably predicts what's produced.
"But trying to mimic a larger swell by generating steep waves unleashes nonlinear forces, including turbulence; a thin, slow-moving layer atop the swell ('the boundary layer'); and oscillations of the entire water body called seiching."
Because Slater and Fincham were essentially the first to try to scale up to the size of a surfing pool, the pair was charting a new path.
"They began in a laboratory wave tank," Cohen writes. "Whereas many wave pools use paddles, plungers, caissons, or other strategies to effectively throw water into the air, Fincham's team designed a hydrofoil that is partially submerged in water. As it cuts through the pool, the hydrofoil moves water to the side (but not upward) and then pulls back on the forming wave to 'recover' some of the water it pushed away. The result is what physicists call a solitary wave, or soliton, that mimics an individual swell in the open ocean.
"Then Slater's surfing experience came in. 'It was [Fincham's] job to figure out how to make that swell, and it was my job to figure out how to break that swell,' he says. It takes a shallow 'reef' of just the right shape to turn a swell into a surfing wave. To fine-tune the shape of the pool bottom, the team relied on Slater's input and on massively parallel supercomputers that often had to run for weeks at a time to complete a simulation. In silico, a wave is a mesh of millions of cells that represent air and fluid."
At that point, it was time to bring their massive mechanical experiment to the ranch, where the building and experimentation came in. The World Surf League purchased a controlling stake, and more dreams were born from the one, farm-bound pool. Not just of what's possible on the wave -- like Gilmore's 14-second tube ride at the Future Classic -- but of what elite-level training and business ventures could look like.
For Fincham, who learned to surf when he began working at USC, the possibilities transcend what most surfers can even conjure in their minds -- like loop-de-loops in the barrel. "We've got the perfect natural wave, and, well, that's cool," he told Science. "But what about a supernatural wave that almost defies nature?"
For now, though, by all accounts, those who have tried their hand at Slater's dream wave are more than content with how it breaks now. As a grinning Gabe Medina said after his run at the September event, "It's going to be great for the sport. It's a fun wave...hopefully the wave will do competitions soon. This is the future."
To read more on the mechanics of Slater's wave, check out the new story in Science magazine.