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A New Lease On Internal Combustion
Somnus suggests we check out the latest issue of MIT's Technology Review, where researchers describe how they can dramatically boost engine output and efficiency by preventing pre-ignition, or "knock." How they do it: "Both turbocharging and direct injection are preexisting technologies, and neither looks particularly impressive... by combining them, and augmenting them with a novel way to use a small amount of ethanol, Cohn and his colleagues have created a design that they believe could triple the power of a test engine."
...become simpler with the addition of a small amount of ethanol.
In a large glass.
Congratulations You've discovered the same thing as Rudolph Diesel except that you don't quite have it right. You don't need to use ethanol or port injection ditch both of those and use good ol fashioned vegetable oil. 0 preignition and you can turn the boost way up on a tiny engine.
This sounds an awful lot like a modern diesel engine. Modern diesels are turbocharged and use common-rail injection to achieve insane pressures at the injector heads (for really fine atomisation of the fuel), which directly inject into the cylinder. I believe the newer engines even stagger the injection during the compression and combustion cycles too to achieve more power and cleaner burning.
(NB: I'm not a revhead so I might be talking shit)
This should be a lot more accurate than the original summary.
Blah blah sig blah blah blah irony blah blah
"People in the tuning industry have been controlling "knock" in various ways for a long time."
Exactly. This sounds a lot like water injection, which has been around forever and does increase mpg by about 10% in turbo cars and allows lower octane fuel.
Here's what's going to kill the technology from TFA:
"Ethanol would be stored in its own tank or compartment and would be introduced by a separate direct-injection system. The ethanol would have to be replenished only once every few months, roughly as often as the oil is changed. A vehicle that used this approach would operate around 25 percent more efficiently than a vehicle with a conventional engine."
This is exactly like water-injection and it's why we don't see water-injection in vehicles. No one wants to have a separate tank that we need to remember to fill-up, and the 10% increase provided by water just isn't enough. This is the same story except it's ethanol, not as easy to find as water, and it's 25% better mpg instead of 10%.
We will never see a production ethanol injection vehicle. Vaporware with a capital V
my karma will be here long after I'm gone
From TFA (and this goes for the reply above mine as well as the parent):
"Similar approaches, some of which used water to cool the cylinder, had been tried before. But the combination of direct injection and ethanol, Cohn says, had much more dramatic results."
Show me someone in the tuning industry using directly injected ethanol along with a turbocharger and regular gas. I've never heard of this approach.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
It might be a while. They're still busy relocating Jimmy Hoffa's body, plotting out new wars in the Middle East, and assassinating more people connected to the moon landing hoax.
Assuming ethanol comes from murdered children and the hydrogen from magic, hydrogen saves 132% more lives than ethanol.
I was thinking the same thing when I started reading the article. A quick search at any of the major car enthusiast websites will lead you to dozens of threads on direct injection and forced induction (turbocharging). This isn't news. There are already direct injection, turboed factory motors out there. The 2007 Saturn Sky Red Line, for example, is powered by a 2.0-liter direct injection turbo engine. You may have heard of another auto manufacturer using this same technology in it's diesel engines... VW's TDI (Turbo Direct Injection).
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The "new" part comes where they are using ethanol direct injection. It's a new twist on an old idea. See also water-methanol injection:
http://en.wikipedia.org/wiki/Water_injection_(eng
Sure, it's not anything evolutionary. And the article might read like 1st Grade literature for anyone who is familiar with cars and tuning... but it's still interesting stuff.
But the story is different because the system will know what to do when it runs out of ethanol, which is to say retard timing and reduce mileage and power output until you add more ethanol. Water injection is aftermarket and usually not compensated for automatically.
The mileage improvement is pretty compelling and I think we'll see it implemented if fuel prices rise much more.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
The '07 MINI Cooper'S has a 4 cylinder 1.6 liter direct-injected twin-turbocharged engine - and since most fuel in the US now contains 10% ethanol, I'd say the "experimental" technology these guys are pushing is already out there in at least one production car. The problem with knocking has been nailed a bazillion years ago - just about all modern cars have an anti-knock sensor that can richen the mixture if it detects signs of knocking - but with high octane gasoline - it only very rarely has to actually do that - so the "problem" of knocking isn't really there. The only time the MINI actually does something like that is when the dumb user filled the thing with regular low-octane gas instead of 'the good stuff'.
Add to that that the MINI has goodies like electric oil, power steering and water pumps that can actually be turned off (rather than merely bypassed) when not needed - so the engine reaches it's most efficient temperature faster and you aren't burning fuel circulating fluids that don't need to be circulated yet. It has computer controlled inlet and exhaust valves - so the timing is infinitely variable - and can be varied separately for each cylinder. For short bursts of accelleration, the car has an 'overboost' feature from the turbo - which won't help you much for prolonged hard accelleration - but is great for a rapid burst of speed for overtaking, blasting out of a corner (FUN!) or blowing away those bloody ugly Scion xB's at traffic lights (a personal mission of mine, I might add).
www.sjbaker.org
You either need to read the article or, if you have, brush up on your reading comprehension skills. The technique used in the article is supposed to allow them to push the turbo pressure much higher than any modern car can handle, even when using high octane fuel. They're talking about using a separate direct injection system to pump a small amount of pure ethanol into the cylinder out of phase with the gasoline. It would cool the cylinder enough to stop knock when the gas is injected at extreme pressures. Supposedly, you would have to replace the ethanol about as often as you have to replace the oil (every few months).
Next time, please try reading the article instead of seeing "ethanol" and "turbocharger" in the summary and shooting your mouth off.
-GameMaster
Rules of Conduct:
#1 - The DM is always right.
#2 - If the DM is wrong, see rule #1
and 90% of cars should be much smaller,
Americans would never accept that. You might as well just say "and fairy princesses should fly down from candyland and give us all ponies to ride."
I think a more realistic possibility is that vehicles will just get much lighter. As an example, if Boeing can make the Dreamliner out of carbon fibre, perhaps it's not that long before we start seing reasonably priced, mass-produced carbon fibre car bodies. There's also reasonably good odds of significant price reduction in titanium and titanium alloys, and aluminium use is becoming more widespread in the automotive industry.
My ideal "dream" situation? A "grid" transportation system, in which vehicles are networked together without any humans behind the wheel (except "offroad"). electric vehicles which get their power from the road (standing wave transmission, perhaps). Autoconvoying and optimized speeds to greatly reduce traffic, increase road capacity, and reduce wind resistance. With vehicles much lighter from being pure-electric without need for even carrying the power source, high speed "bulletways" with coils of wire embedded in them, so that vehicles with halbach arrays (magnetic arrays with highly lopsided fields -- near double-strength on one side, near zero on the other) can employ "Inductrac" style maglev, eliminating rolling losses and having very little maglev losses at high speeds.
* Greatly reduced wind resistance and no rolling losses.
* Still your own, personal vehicle (the profiles would likely be a bit different from present day for optimal convoying, though)
* Never having to drive. Play, sleep, work, chat, whatever during the trip.
* Less need for roads eating up cityspace
* Less traffic
* Much faster travel, to the degree that airlines would be needed much less often.
* Much less energy use
* Independent of oil.
* No need to even be in your vehicle while it's moving -- automated delivery, automated pickup of your kids or groceries (if the store will load for you), etc.
* The great economic benefits of travel being automated and fast.
* Much less space used up downtown for parking, as vehicles can drive themselves to and from less convenient parking without you.
* No speeding tickets
* Very few accidents (no human error, no drunk driving, etc)
The benefits go on, and on, and on. Unfortunately, we have all of our existing infrastructure to deal with. Thankfully, it can be moved towards in stages. First hybrids, then plugin hybrids, then electrics, then grid-power electrics. First radar-assisted braking (like we have now), then wireless transponders to assist traffic, then increasing wireless information exchange and planning. Once vehicles are light enough, all-electric, and are designed for high-speeds with automated operation, inductrac-style maglev becomes realistic for long stretches.
Assuming ethanol comes from murdered children and the hydrogen from magic, hydrogen saves 132% more lives than ethanol.
I'm not sure I'd put that in the "benefit" column. I enjoy driving. What I fear most when people start talking about future transportation technology is that almost everybody assumes that driving is a chore and nobody should have to do it anymore. While it would be great to get the people who don't like driving off the road (the people who eat, read, do their makeup, change clothes, etc all while driving), if the solution involves removing my own ability to drive then I'm against it.
Note that I didn't say anything about what I would drive. Electric, hybrid, magnetic, petrol, whatever, I'm fine with it as long as I'm allowed to stay in control of my personal vehicle.
Other people have different things to say about Cobasys:
And this, which killed the electric RAV4:There's plenty more, just perform the search suggested at the first link.
It appears likely that the advances in Li-ion and carbon-backed lead-acid will make it far more difficult to keep the next round of batteries out of vehicles. Regardless, the delay in availability of mass-market PHEV's and EV's has meant many billions or tens of billions of dollars in additional revenue for the oil companies and oil exporting nations. (The current administration shares responsibility for e.g. terminating the Partnership for a New Generation of Vehicles, which would have delivered 80-MPG sedans about.... now.)
The take-home lesson? Don't believe everything you read.
Sustainability and energy independence essay
"...limiting their power"
Harsh. Apparently someone hasn't been keeping up on Diesel Technology lately. You know it was an Audi Diesel that one the last LeMans right?
I dirve a little VW Golf TDI. 115hp is nothing special, but 175 lbs/ft of torque is enough to get the car moving in a hurry. The car is almost as quick stock as my '88 Fiero with a 3.4l V6 (about 180 hp and 175lbs/ft).
When you have an engine that can (lightly/medium modded) put out 250 lbs/ft or torque from 1800rpm to 3500rpm, the concern is less about RPM and more about Gearing and shifting. Have you seen the new VW/Audi dual clutch manual automatic trannys? Their 6 speed DSG auto transmissions can upshift in 8ms. With that wide of gear range, and that fast of shifting, having a somewhat* limited rpm band is not an issue.
*I say somewhat because the vast, vast majority of drivers will never spin their engine over 3500 rpm. Hondas, Subarus, what have you, they are all designed (stock) as commuter vehicles. And if you have to turn 7k rpms to get your car off the line, it's not going to hold up to daily driving.
-Rick
"Most people in the U.S. wouldn't know they live in a tyrannical state if it walked up and grabbed their junk." - MyFirs