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Scientists Claim Major Leap in Engine Design
An anonymous reader writes "Purdue researchers say they have made a major advance in the design of the internal combustion engine, one that could seriously boost fuel efficiency and cut emissions. A key portion involves building intake and exhaust valves that are no longer driven by mechanisms connected to the pistons, a departure from the way car engines have worked since they were commercialized more than a century ago. 'The concept, known as variable valve actuation, would enable significant improvements in conventional gasoline and diesel engines used in cars and trucks and for applications such as generators, he said. The technique also enables the introduction of an advanced method called homogeneous charge compression ignition, or HCCI, which would allow the United States to drastically reduce its dependence on foreign oil and the production of harmful exhaust emissions. The homogeneous charge compression ignition technique would make it possible to improve the efficiency of gasoline engines by 15 percent to 20 percent, making them as efficient as diesel engines while nearly eliminating smog-generating nitrogen oxides, Shaver said.'"
Wankel wants his engine back, and what happens when the 'valved' design that's non-mechanical fails(not piston timed). I hate to say this but anyone who's apprenticed as a mechanic, rebuilt any type of engine or worked on one can tell you that the more computerized crap they stick in cars, the more prone to failure they'll become.
KISS is running out of the automotive industry to ensure that dealerships continue to get their pay.
Om, nomnomnom...
I don't see anything new here. They mention variable valve timing, which is already here, and exhaust gas recirculation, but they're giving it another name, and something like the Miller-cycle engine.
Some of these tweaks are better suited to locomotive engines or other constant RPM power plants. But, overall, they're just combining some well known techniques.
I hope something comes of the VVT stuff. That's where some real gains can be made, especially to help implement a better Miller-cycle engine.
They could also implement Honda's CVCC techniques or the stratified combustion chamber technique to burn low grade fuels. That would help a lot.
Best regards.
Beware -- any time you see "..which would allow the United States to drastically reduce its dependence on foreign oil and the production of harmful exhaust emissions," it is marketing language designed to appease ignorant masses, investors, and assure loyal Republican investors that "they are with the program".
P olicy.pdf
And this program is the US energy policy.
http://www.whitehouse.gov/energy/National-Energy-
In case you are lazy, the economic numbers behind these 170 pages say basically:
- we're expanding our "energy" supply; ie volume of foreign oil fields
- we've secured iraqi fields for better exploitation
- we're converting our military to a more mobile fighting platform to secure remote oil
- we ain't reducin' nothin' as far as consumption and conservation goes
- anwr holds only a few drops in the vast sea of petroleum - it's a pawn of environmentalogists (as opposed to environmentalists)
Reduction of dependence on foreign oil? We passed escaping that point more than a decade ago (50% imported vs domestic). Ask yourselves why president Reagan removed the solar panels from the White House the moment he moved in. Our energy policy means we're going to take foreign oil and god help those who stand in our way.
Or not. (Very NSFW.)
Mal-2
How is the Riemann zeta function like Trump rallies? Both have an endless number of trivial zeros.
Some is. Some is not. Steel rusts. Rubber rots. Exhausts and such will require replacement even if you don't drive often.
I disagree. Steel only rusts when exposed to moisture, and is uncoated. Are you parking in a pond? As long as your car is painted, you shouldn't have a problem. Maybe if you're parked next to the ocean or something, you might have accelerated corrosion, but most people should be fine.
Rubber does rot, I'll give you that. Even so, you probably won't notice many problems, other than possibly some coolant hoses leaking and needing replacement. I live in a desert, so I know a little bit about rubber failing.
Exhausts? No, exhaust systems are nothing more than metal pipes, and do not need replacement when not used. Where you can have a problem is if you take extremely short trips, so the engine doesn't have time to warm up: water will collect in the exhaust during the first few minutes of use, and when the car fully warms up, the exhaust gets hot and the water evaporates. If you don't drive long enough to hit that stage, you accelerate the corrosion of the exhaust system.
And gasoline doesn't keep well while it's in a fuel system. In industrial containers, it'll keep indefinately. In a car, it only keeps a few weeks.
I think you're exaggerating things a little here. I regularly left my car unused for weeks at a time when I was in college and never had fuel problems. Yes, if you leave a car for a year, you'll probably have a problem, but a few weeks, no.
Have one parking space? Get fucked.
Writers imply. Readers infer.
When gas hits 6 or 7 dollars/gallon, you're going to wishing you had something with at least double the fuel efficiency of your current vehicle for going to work every day. We're past $3 now and heading quickly for $4. I have to laugh when I pull into a gas station and see $90 totals on the other pumps.
We're going to need horsepower to survive the future!