The Technology That Helps Make Your Car More Aerodynamic? It’s Been Around Since The 1800s

Illustration for article titled The Technology That Helps Make Your Car More Aerodynamic? It’s Been Around Since The 1800s

Happy Sunday! Welcome to Holy Shift, where we highlight big innovations in the auto and racing industries each week—whether they be necessary or simply for comfort.

Advertisement

Without aerodynamics, cars—and airplanes, spacecraft, even bobsledders—are just objects displacing wind. Displacing wind inefficiently, at that. Learning how to maneuver aerodynamic drag on those objects usually warrants a trip to the wind tunnel, where engineers test the most minute of aerodynamic details.

But don’t be fooled by the innovative capabilities of the wind tunnel. The device surfaced long before the automotive industry gained a footing, with its creation dating back to 1871. Yes, even Wilbur and Orville Wright had one.

Advertisement

Before automakers and race engineers began to refine their craftsmanship in the tunnel, aeronautics pioneers developed it in order to make attempts at flight. That’s right—there weren’t functioning airplanes to test at the time that the tunnel came about.

The Wright brothers developed their own wind tunnel in 1901, in which History reports that the pair tested “nearly 200 wings and airframes of different shapes and designs.” The first flight came over 30 years after the original wind tunnel in 1903, when the Wright brothers kept their craft afloat for 12 seconds.

The wind tunnel wasn’t the first tool by which to evaluate plane functionality, though. Following “unhappy experiences” with an apparatus that the came around in the mid 1700s, the “whirling arm,” Frank Wenham sought funding to create a new, better device. One that remains relevant today. From NASA:

That something better was a “wind tunnel.” This utterly simple device consists of an enclosed passage through which air is driven by a fan or any appropriate drive system. The heart of the wind tunnel is the test section, in which a scale model is supported in a carefully controlled airstream, which produces a flow of air about the model ...

Advertisement

Testing within wind tunnels became an essential part of World War II, according to the University of Washington Department of Aeronautics and Astronautics. Once the war use wound down a bit, race engineers caught onto the technology and and passenger cars followed after.

Aerodynamics can take performance vehicles and race cars from the boxy, high-drag body styles to the downforce-ridden ones we see today (which, in the case of certain race cars, can be considered less than good), but the testing that goes into speeding those cars up is done without any actual vehicle movement in the tunnel. The car just parks it, and in come the winds. From HowStuffWorks Auto:

The car or plane inside never moves, but the fans create wind at different speeds to simulate real-world conditions. Sometimes a real car won’t even be used — designers often rely on exact scale models of their vehicles to measure wind resistance. As wind moves over the car in the tunnel, computers are used to calculate the drag coefficient.

Advertisement

Modern-day wind tunnels are essentially just a giant, enclosed hair dryer for your car, minus the heat (and split ends, hopefully). A wind tunnel located in North Carolina—in other words, NASCAR central—even has what can only be described as a car treadmill inside, capable of simulating speeds at 180 mph.

According to Gizmag, NASCAR and Formula One owner Gene Haas put $40 million into building the facility. It’s called the Windshear tunnel, and opened back in 2008. Here’s a look at a typical session there:

Boy, have things gotten fancy since the first attempts at wind tunnels. Things continue to get fancier as well—according to How Stuff Works Science, plenty of “wind tunnel” testing occurs on computers these days. In those cases, a trip to the actual wind tunnel is to back up the simulated test results.

Advertisement

That same kind of approach also made its way into crash testing, as computer simulation continues to become more popular for running test wrecks, making tweaks to the design and running them once again. Constructing full-size wind tunnels—and crashing vehicles—is expensive, and testing in the virtual world saves a buck or two (maybe a few more).

But, as grandma will always say, “the real world is better than those computers you kids play on all day.” If there’s any reason to keep the real-world testing around, it’s just plain cool.

Advertisement

If you have suggestions for future innovations to be featured on Holy Shift—in street cars, the racing industry or whatever you’d like—feel free to send an email to the address below or leave them in the comments section. The topic range is broad, so don’t hesitate with your ideas.


Photo credit: Bill Pugliano/Stringer/Getty Images

Contact the author at alanis.king@jalopnik.com.

Share This Story

Get our newsletter

DISCUSSION

rockbottom81
Rock Bottom

Thanks for writing this. I’m an aerodynamicist at one of the Big 3 (Big 2.5 these days) and I always love seeing our craft get exposure!

I will say that the most interesting thing I’ve noticed since coming to the auto industry from the aerospace industry is that each brand’s cars aero features seem to be shaped by that company’s wind tunnel. Every tunnel works a little different and that is reflected in the cars that are designed there. GM have a large closed jet tunnel (pictured in the leading photo) while Ford and FCA have open jet tunnels, like Wind Shear. In addition, we all use Wind Shear, and so do some of the Japanese car companies.

Having said all that, we all buy and test cars from our competitors in our own wind tunnels. It’s always been done, not a secret, and we often even meet up with our competitors and talk about what we find. What I’ve noticed is that sometimes GM might have a feature on their vehicles, like underbody shields, that doesn’t seem to work in the Ford or FCA tunnel. At the same time, Ford might have a flow “kick” at the rear of the car that doesn’t have much effect in FCA’s or GM’s tunnels. These features are all designed based on data the aerodynamicists collect in their own tunnel, every tunnel is a little different, and that difference is reflected in (and effects) the details of the design. This fascinates the hell out of me!

It’s no secret that cars have been in wind tunnels for decades. Ford started testing full size cars in the late 1930s, I think Chrysler started around that time with sub-scale models. FKFS in Germany claims they were testing cars in the 1930s as well. Even looking at the facilities out there right now, GMs tunnel is around 40 years old and still going strong. Ford and GM both built new tunnels in the early 2000s, and almost every German and Japanese manufacturer has invested in new tunnels in the past 15 or so years. The craft is evolving, just like CFD, and will continue to do so for the foreseeable future.

Next time you go to an auto show, compare the shapes of various parts on, say, pickup trucks. Look for things that are obviously there for aero reasons, not just styling. Think of airdams, tailgate tops, the shape of contours in the tail lights, placement of underbody shields, etc. Look at how Ford, GM, FCA, Nissan, Toyota, etc all do it differently. They all want the same thing, but are using different tools to design their way there.