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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."
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.
"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.
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.
Who gives two shits about making petrol engines 25% more efficient when Diesels are already 50% better in practical applications.
Once again, this just shows that what Americans don't know about car technology could just about be crammed into the Grand Canyon.
Volkswagen already have quite a few turbocharged FSI petrol and Diesel engines - take a look at how efficient they are before swallowing this MIT bullshit.