Road and Track, July 2nd, 2006
Can You Read Me Now?
A team of traffic-safety specialists, graphic artists, psychologists and vision experts have developed a new typeface specifi cally designed for highway signage. Ten years in the making, ClearviewHwy has now been approved by the Federal Highway Administration. It’s already appearing in Pennsylvania and Texas, with other states adopting it in time.
This particular typeface is designed to enhance legibility and improve ease of recognition. Indeed, specialists make an interesting distinction between these two. Legibility involves an unknown posting that we identify by its letters and compose its words. With recognition, the driver already knows the name being sought. Researchers note that distances for recognition are typically twice those for legibility.
Another goal of the new font is to reduce halation, the overglow perceived by older drivers and others with reduced contrast sensitivity to high-brightness retro-refl ective materials. Illuminated by headlights, the lower-case letters “a,” “e” and “s” can be particularly pesky.
BUY A CAR SUBCONSCIOUSLY?
Recent research cited in Science, published by the American Association for the Advancement of Science, certainly runs counter to my own personal decision-making: “Tough Decision?” it reads, “Don’t Sweat It.”
That is, researchers at the University of Amsterdam in the Netherlands studied purchase patterns and subsequent buyer satisfaction/ remorse. They found that too much contemplation can actually get in the way of good decision-making, especially when the choice is a complex one.
Conscious analysis, they say, is best directed to simple things like “which socks shall I buy?” But a decision that requires evaluating many factors—choosing a car, for instance—is better handled by the subconscious.
They tested this hypothesis in several ways. First, student vol-unteers were given simplified attributes of four hypothetical cars, and asked after only four minutes’ deliberation which was best. Most participants had no problem identifying the ringer.
Other participants were given a more complex list of attributes, likewise rigged. The best car was identifi ed only 25 percent of the time, no better than chance.
Last, the second experiment was rerun, only this time researchers purposely distracted members of this group for four minutes before asking for their decisions. This time, more than half picked the best car.
Even more compelling, the researchers went into the real world, to IKEA and to Bijenkorf, a Dutch department store. In each, researchers quizzed buyers on two factors: How long had they spent thinking about their purchase. And, several weeks later, how pleased were they with their decision.
For relatively simple buys at Bijenkorf ’s, shoppers who spent more time deliberating were more pleased later on. But for IKEA shoppers making substantially more complex (and more expensive) choices, the opposite was true: Those who reported less deliberation turned out to be the happier.
Faced with a complex decision, researchers conclude, an optimal strategy seems to be to collect relevant information, give these facts good attention at fi rst, and then sit on things to let one’s subconscious do the hard work.
NASCAR IS GOING UNLEADED—FINALLY
Earlier this year, in “Fueling the Competitive Spirit,” January 2006, I lamented that our premier racing series burns our dirtiest fuel. There are lots of reasons for NASCAR’s leaded gasoline, a crucial one being durability of pushrod valve gear at substantial revs and race distances.
Ultimately, though, the EPA, Clean Air Watch and other organizations pressured NASCAR to seek other engineering solutions. And, indeed, the changeover to unleaded gasoline is scheduled for 2008.
Come to think of it, what with Audi’s success at Sebring, maybe by then NASCAR stockers will be diesel-powered.
REPORTED HORSEPOWER AND TORQUE
We get our data panels’ fi gures on horsepower and torque directly from the manufacturers. In horsepower-hype days of yore, we used to joke about bhp standing for “horsepower at the brochure.” Our recently revised SAE standards seem to have cleared up some of the ambiguities pretty well. (See this column, November 2005.)
A new one has cropped up, however. Manufacturers are justly proud of their engines’ extended torque range, and many are reporting this with phrases such as “300 lb.-ft. of torque from 2000–4000 rpm.” Note, this is in marked contrast to previous reporting of peak torque, specifi cally at a single engine speed: for instance, “345 lb.-ft. of torque at 3500 rpm.”
With the first example, there’s an implied “at least” in the reporting. That is, the torque curve isn’t utterly fl at at precisely 300 lb.- ft. all the way from 2000 to 4000 rpm. Rather, and still a commendable achievement, it’s no less than 300 over this range.
By contrast, the peak fi gure is just that: a maximum.
As part of this, be aware that there’s a direct relationship between horsepower and torque: In our English units, torque x rpm bhp = 5252
Thus, if the dynamometer reads 325 lb.-ft. of torque at 3700 rpm, then this engine is producing 229 bhp at this rpm. If its peak horsepower is, say, 300 bhp at 6500 rpm, then you can work backward to fi nd the torque at that engine speed: bhp x 5252 torque = rpm or 242 lb.-ft. of torque (apparently well past its peak).
CHOO-CHOO VROOM?
BMW is developing a steam-driven auxiliary power unit, one that’s said to capture 80 percent of the heat energy in the exhaust. Test-rig trials with a 1.8-liter 4-cylinder have reduced fuel consumption by 15 percent—and generated an added 13 bhp and 15 lb.-ft. of torque.
As I learned not long ago (see “Technology Insight: Your Mileage May Differ,” May 2006), the fuel burn in a modern engine is something like 99-percent effi cient. The basic ineffi ciencies of internal combustion are traceable to heat transferred to the coolant or sent out the exhaust. BMW’s Turbosteamer exploits some of this heat with two fluid-circulating systems.
The primary one pumps water through a heat exchanger adjacent to the catalytic converter. Water in this circuit is heated to a super-steam 1022 degrees Fahrenheit.
This steam is converted to mechanical energy in an expander (essentially, a swash-plate device not unlike an a/c compressor), the output of which is transferred by belt drive to the crankshaft. Remaining heat is routed to another exchanger where a second circuit, this one ethanol-charged, feeds a second expander.
The idea of a steam auxiliary drive dates from 1914. BMW’s real achievement is in its feasible packaging. Burkhard Goeschel, BMW R&D guru, said the Turbosteamer could be in production by the beginning of the next decade.
STOMPIN’ JACK FLASH
Mercedes-Benz has received approval from the National Highway Traffic Safety Administration to give its emergencyfl ashing brake lights a two-year tryout in this country. Activated only when the brake pedal is really mashed, the system replaces steady illumination with a pulsing red, the point being to alert those behind that more than ordinary braking is under way.
This feature is already available in European- market S-Class, CL-Class and SL-Class cars. It needed NHTSA exemption because the U.S. rule requires steady illumination.
CATALYST DUO TO THE FORE
A catalyst, you may recall, promotes a chemical reaction without actually getting involved itself. This is very much like my own personal experience in chemistry class, but that’s another story entirely.
As reported in Science, the weekly magazine of the American Association for the Advancement of Science, researchers at Rutgers University and the University of North Carolina, Chapel Hill, have devised a pair of catalysts that might transform gasoline into something of a renewable fuel.
The catalysts promote fuel production from alkanes, relatively useless byproducts of the hydrocarbon cracking process. Briefly, the idea of cracking is to turn longchain hydrocarbons into medium-size ones like diesel fuel and shorter ones like gasoline. These alkanes are very short ones and far less useful.
This new catalyst duo transforms alkanes into a useful transportation fuel. What’s more, the catalysts might also prove productive with feed stocks as varied as coal, tar sands and renewable biomass.
Other researchers, these at the University of Wisconsin, Madison, have developed a catalytically enhanced transformation of plant matter to hexane, the new duo then turning the hexane into gasoline and diesel.
Alas, at the moment, the catalysts work too slowly (again, reminding me of my Chem 101). Researchers are working to resolve this commercial shortcoming.
OSU CAMPUS IS PART OF THE HYDROGEN HIGHWAY
The Ohio State University’s Center for Automotive Research has opened the fi rst hydrogen refueling station in that state. The OSU CAR hydrogen refueling station is one of around 15 in the country. This may not seem like many, but it’s a start.
ELECTROLYSIS WILL COME, BUT IT’S NO SLAM-DUNK
I’ve been a fan of hydrogen generation through the electrolysis of water. Gee, I even did this back in Chem 101.
Oops, given my earlier reference to catalysts, I best not dwell on this. But I suspect you know the experiment: Pass a current through a dish of water. At the negative electrode, the cathode, you’ll accumulate bubbles of hydrogen. At the positive electrode, the anode, oxygen will come off.
I’ve learned recently that this neat little lab experiment isn’t exactly what’s in mind when real-world production of hydrogen is envisioned. For one thing, electrolysis is extremely energy-intensive. I think of this as an engineering problem, though, not a conceptual one. Solar, wind, geothermal, clean nuclear; there are many potential sources being explored that could support electrolysis.
The conceptual challenge, however, has to do with upscaling my nice little dish of good clean water. Apparently, real-world water to fuel-cell-acceptable hydrogen isn’t as simple as in Chem 101.
As this technology evolves, our initial supplies of hydrogen will continue to come from natural gas, not from electrolysis.
