By Margie Church, Editor
Heads up surfer wannabes! this is your chance to try the sport successfully without landing yourself in the ER or on an episode of ABc’s America’s Funniest Home videos. American Wave Machines has developed a unique standing wave surf pool that lets people of all ages and experience surf or body board in a safe, controlled way. This isn’t the sheet flow water ride that you may have seen at waterparks and on cruise ships. the surfstream simulates a stationary, 3-foot-tall, standing river wave with water that moves at a natural, gravity-driven speed. Multiple riders share the wave and real surfboards are used to the delight of waterpark owners and their guests.
Bruce McFarland, President of American Wave Machines, is a surfer and an aerospace engineer. His interest in waterpark attractions led him to help develop the sheet flow water ride in which the wave is shaped primarily by the shape of bottom. McFarland is fascinated by waves, and standing waves, which are shaped by the water itself and offer a naturally changing and dynamic surf environment. On the hunt for new ways to apply his engineering background to waterpark attractions, McFarland met Kenneth D. Hill. Hill showed McFarland a video of standing waves occurring at the Waimea River mouth in Hawaii. It’s a transitionary phenomenon that occurs during the rainy season with the help of Mother Nature and a few ambitious surfers.
“When I saw Hill’s video, the light bulb immediately came on,” McFarland said. “the video showed the natural beauty and dynamic variations of the wave’s shape and behavior without it actually moving upstream or downstream. If we could recreate that, I thought it would be a great product for a waterpark.”
How to accomplish it was the puzzle McFarland and Hill couldn’t wait to solve.
Hill had been sharing his idea with waterpark owners but disinterest found him at every turn. surfing as a waterpark attraction wasn’t fully embraced because of insurance issues and wave pools full of people bring substantially higher ticket sales. surfing is also very challenging for participants and very active compared to the passive, floating rides in wave pools. this made the concept’s economics a significant hurdle.
Undaunted, McFarland began building prototypes in his test facility. one day, after about six months of pure trial and error, a wave “popped” out of the channel. “It was stable and smooth,” McFarland said. “I was ecstatic!”
McFarland videotaped the wave action, recorded the flow rates, and built a second larger model. It didn’t work. He couldn’t understand why, so he decided to rebuild the original model with allits tin, tape, and magnets. “the wave formed again,” he said. “As I looked more closely, I noticed that when I ran the water over the tin, the shape of the water flow changed the shape of metal foils. It was the Bernoulli effect in action.”
The Bernoulli effect is the decrease in internal pressure of a fluid as it increases in velocity. A common illustration is how air flows around an airplane wing to create lift. the shape of an airplane’s wings creates a Bernoulli effect, during which the air flows faster over the top of the wing (and decreases in density) than the air flowing below. The higher-pressure air below the wing therefore pushes the wing upward, creating lift. In McFarland’s model of the water channel, the Bernoulli effect was helping to create the wave. Once McFarland recognized this, he was able to develop a successful full-scale version. the full-scale steel prototype, named surfstream, was demonstrated for potential customers, in a private setting, with people of all ages using it. McFarland viewed surfstream as a complimentary product (to a wave pool or sheet flow rider) that reached a wider demographic. He said it is much easier to learn to surf or body board on the surfstream than in the ocean. The 3-foot wave depth and slowness of the water allows for fins on the surfboard, which is a key to real surfing action. Beginners learn about balance and how to properly place the board in the wave, whereas more experienced surfers can try maneuvers. “It’s easier to have success using surfstream and if one enjoys the experience, the skills learned are transferable to ocean surfing,” he said. several surfers can ride the wave simultaneously, making it more economically attractive. “We surpassed all the expectations for surfstream to be fun, easy, safe, and economically feasible,” McFarland said.
Although SurfStream uses a steel frame, its surface, known as the flume system, is FRP. McFarland chose Steve Ream, Owner of Fiber Reinforced Products, to produce SurfStream’s fiberglass flume system components. Ream has 30 years experience in mold making, fabricating, and FRP repair in almost any composites application you can name. His specific experience in the aerospace industry appealed to McFarland. “The aerospace industry is extremely demanding when it comes to performance and quality,” McFarland said. “I wanted that in my product.”
Ream selected Interplastic’s CoREZYN® vinyl ester barrier coat for osmotic protection and good surface quality. CoREZYN marine grade polyester resin with alternating layers of OCV (formerly Saint-Gobain Vetrotex) chopped strand mat and CPIC 18-ounce woven roving provide bi-directional strength. Half-inch Lantor CoreMat® eliminates oil canning — the flexing or deflection of a flat surface. “Normally we’d just use 3/8-inch core material,” Ream said, “but we wanted to build strength without adding a lot more weight.” CoREZYN iso/NPG® gel coat provides UV protection and helps retain the surface finish.
All told, 24 individual molds, which Ream also fabricated, are needed to build 97 flume system components. Fully assembled, Surf-Stream is 20-feet wide by 40-feet long and fits in an above-ground or an in-ground, water-filled, concrete pool. The “riverbank” is an area where surfers await their turn. The flume is supported by the pool’s concrete walls and its FRP parts average 4-feet wide by 5-feet long. The interior part walls are tapered roughly from 5.5-feet wide by 5-feet long to a 5-foot wide by 2-foot long wall. In the center of the “wave” is a foil shape for water return. All of the parts have a mating return edge with drilled 9/16-inch holes for ½-inch stainless steel bolting underneath. Ream estimates two months production time for each SurfStream. Surprisingly, SurfStream is portable. It is designed and built to accommodate shipping restrictions, allows assembly by just two people, and can be stored if necessary. Assembly of the entire product takes a week.
McFarland expects to build about 10 Surf-Streams in 2008. He realizes that will require additional manufacturing space and other business challenges. It’s a good problem to have, he said. “Part of our growth opportunity is helping to create a new market at waterparks,” McFarland said. “The sports or surf venue, which is dedicated to challenge activities such as surfing and rollerblading. That is where we’re setting our sights. SurfStream is a very compatible attraction with them.”