800 MPH or 100 MPG

By Steve Robbins


John Busa

Americans have interesting relationships with their cars. My wife, for example, still has her 1985 Volkswagen Jetta diesel under a tarp in front of one of our barns. I had it restored for her a few years ago, and even with 155,000 miles on it, it ran pretty well. She loves that vehicle and although it doesn't see much use, it won't be going anywhere any time soon.

I am totally the opposite. I look at an automobile as a tool. When it reaches the end of its design lifecycle, I gladly exchange it for another. A lot of factors come into play when I make a decision on what to drive. Living in New Hampshire on a dirt back road, I look at ground clearance and AWD traction. My Volvo XC70 is a tank, but has much better fuel efficiency than one of those SUV beasts weighting around 4 tons. It even drives like a sports car.

Going to Extremes
A couple of years ago we ran a cover story on a team of North American engineers who designed and built a vehicle that could break the world land-speed record of 763mph. This “car,” built by North American Eagle (NAE), was designed on the converted airframe of an F-104 Starfighter. This vehicle would never make it to my home in the middle of a New Hampshire winter, but if it could my usual 50-minute commute to work would only take me about 3 minutes and 15 seconds. That's something I would be very interested in.

Last week I was at a Siemens event where I had the good fortune to meet the design team who won the Automotive X-Prize a year ago. They walked away with a cool $5 million for designing and building a mainstream car that could hold four adults with luggage, get more than 100 miles per gallon and have a range of 200 miles. Oh yeah, and it had to have four wheels, pass Consumers Union dynamic safety standards and Tier 2 Bin 8 emissions.

My present car averages about 24 mpg, so my 84-mile daily round trip costs me around $12.77 at today's fuel prices. If I owned an Edison2 VLC (Very Light Car) I would only be shelling out $3.07 a day. This adds up to a savings of $2,425 a year, just for my commute. OK, I'm interested, but it probably isn't going to get me home in the winter either.

These vehicles are designed for extremes of speed and fuel efficiency. One is a bit more practical. We do need 100-mpg cars as soon as possible. On the other hand, I doubt you or I will ever even see an 800-mph car in our future, and it's not just because the NAE speed demon burns 31 gallons of fuel a mile. Still, as the Chinese and Indian consumers begin buying more cars, even 12-mpg SUVs will become art objects.

Weight and Drag
What is interesting is that neither of these projects would ever have been possible without the use of fast computers and analysis software. Early in the design phase, the Edison2 team realized there were only two variables that they needed to pay attention to if they were going to win that prize: weight and low aerodynamic drag. Multiple designs and computational fluid dynamics (CFD) simulations later, Edison rolled out an 850-lb sleek machine that was one of the most aerodynamic automobiles ever tested. And, it was designed to be converted into a vehicle you or I can afford to use. Target price for a consumer model is under $20,000! Not too bad for a fuel-efficient car that runs on a 250cc turbocharged, one cylinder engine that can drive the VLC from 0-60 in 15 seconds. You know, if I lived in California, I think I would buy one.

The NAE used CFD and finite element analysis (FEA) to keep the car on the ground. Also, on a car going that fast, brakes become very important. It took new technology to keep the brakes from melting and catching on fire. I don't think weight was a factor as they weren't into the fuel efficiency game.

Looking back on the purchase of my wife's 1985 Volkswagen, it was very innovative for the time. It normally gets more than 50 mpg, twice that of my Volvo. Maybe I should talk her into giving it to me. It will make it up my road in all but the worst of weather, and I would keep the XC70 for snowy days.

Steve Robbins is the CEO of Level 5 Communications and executive editor of DE. Send comments about this subject to de-editors@digitaleng.news.

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