Gas wins (again)
By Robert Cumberford, Ronald Ahrens
Credit: Automobile Magazine (http://www.automobilemag.com)
So much for alternative energies as the immediate future of the automobile. The solution that beat out steam and electricity a hundred years ago wins again -- and not just by using a high-energy-content liquid (in this case E85) to fuel an internal-combustion engine, but also by embracing the formula espoused by Henry Ford, Ettore Bugatti, Colin Chapman, and many others: keep vehicle weight low. Add greatly reduced aerodynamic drag, and you have the whole philosophy, as most elegantly expressed by Felice Bianchi Anderloni, founder of Carrozzeria Touring: weight is the enemy, air resistance the obstacle.
The Edison2 team took those words to heart, winning the $5 million mainstream class of the Progressive Insurance Automotive X Prize by demonstrating 100-mpg capability with a four-passenger, four-wheel car. At 830 pounds, the Edison2 Very Light Car gets by with a 40-hp single-cylinder engine. No, it's not a "real" car, not yet. Give it 5-mph bumpers, an adequate HVAC system, a radio, and a navigation system, and you might have to accept 1000 pounds. Then add a second cylinder to get 60 hp, and you might have to accept "only" 80 mpg in normal use.
Think of the weight and size reductions we have all seen in electronic products. The Apple iPad weighs less than 26 ounces and can perform many of the functions we expect in cars, including navigation. The passenger compartment of the Very Light Car is easier to heat and cool than those in SUVs or minivans, but it will also seem cramped to people who aren't accustomed to light-airplane cabins, which is clearly the model for the payload nacelle of this vehicle.
The very low -- 0.16 -- drag coefficient is admirable, but not completely without precedent. Back in 1924, the open-wheel Rumpler Tropfenwagen yielded a 0.28 figure -- the same as the new Chevy Volt. Barnaby Wainfan, well known in aeronautical circles for his iconoclastic approach to design, was Edison2's aerodynamicist. He faired the wheels of the Very Light Car in a manner highly reminiscent of Frank Lockhart's brilliant 1928 Stutz Blackhawk Special land-speed-record car, another triumph of intelligent design over convention and brute force.
Wainfan says he tried to introduce a little style to the vehicle. Perhaps so, but right now it stands as a pure engineering exercise, a racing team's pragmatic answer to an extremely difficult challenge. It also looks like it would be tremendous fun to drive. Not bad for an ultraeconomy car.
1. The sleek nose would do honor to a Bonneville racer.
2. The highly rounded, almost domed, roofline keeps airflow attached to the surface, although that flow is surely disturbed by the wiper arm.
3. NACA-type duct avoids disrupting the airstream and ensures adequate cooling for the rear engine.
4. The best way to fair a wheel in 1928 is still the best-and best-looking-way to do the job eighty-two years later.
5. Tall afterbody serves as a fin, keeping the center of pressure behind the center of gravity for stability in crosswinds.
Barnaby Wainfan Northrop Grumman Aerodynamics expert by day, Edison2 shaper by night
"You can snark all you want, but this is physics. What the X Prize did is force us to take another look at the physics."
"There is no magic here. What it is, is a thorough understanding of the physics-and putting a lot of effort into designing a car with the physics of fuel economy foremost in our minds."
"If I were to take two normal license plates and hang them exposed to the air on our car, it would increase the drag by 50 percent."
Credit: Automobile Magazine (http://www.automobilemag.com)
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