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Lotus Teases With a Fuel-Agnostic Two-Stroke Engine
JohnnyBGod writes "Lotus claim to have invented a new, more efficient engine design. The two-stroke, flex-fuel engine can achieve, according to the surprisingly technical press release, 'approximately 10% better [fuel consumption] than current spray-guided direct injection, spark ignition engines.' The engine has a sliding puck arrangement to control its compression ratio, and has direct injection and a wet sump, to eliminate fuel leakage to the exhaust and the need to mix oil with the fuel, two common problems with two-stroke engines. Lotus engineering have released a video explaining the engine's operation."
So where is this magical Ford engine at now? A one-off prototype car is no better than a single experimental engine.
Yes, but keep in mind, it still looked like a Ford Fiesta.
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Don't forget one of the big 2-stroke killers in the USA was the as usual the EPA. Because they set at the emissions requirements as ratios; rather than say an absolute value per horsepower hour. A 2 stroke looks dirty compared to a four stroke if you compare the various amounts of controlled gases in a sample but they are often allot better in absolute terms; because they can do more work per unit of displacement and revolution.
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"In reality, noisy diesels have sold well in Europe "
Speaking as an Englishman and part time car nut: noisy diesels would sell rubbish,
My GF's diesel Ford is quieter above 30mph than my petrol Honda, once you get above about 2000rpm when the turbo starts to kick in the diesel has more torque and the difference in noise is impossible to tell, but the extra torque means that you can rev the diesel lower. At idle my petrol Honda is slightly quieter but the idea of noisy/dirty diesels is old.
Now at peak revs the petrol produces more power and I don't see me putting a diesel engine in my motorbike anytime soon, but for me the competition in none race cars has already been won by the diesel.
Except of course that the last Monte Carlo 24 hour race was won by a diesel...
"The weirdest thing about a mind, is that every answer that you find, is the basis of a brand new cliche" -
Dude, Chill!
Let's assume you're right and it could have been done 30 years ago (it couldn't but I'll get to that later). It's newsworthy because no-one has done this before, in fact it's more newsworthy if someone has a really obvious idea that no-one has done before. I'm sure the first person to stick an internal combustion or steam engine on a cart was told it was a really obvious idea, but the first horseless carriage still deserved to be big news. I'd certainly class a major engine development as being as newsworthy as the latest revision of the Linux kernel being released.
As I understand the article they're using direct injection similar to that used in modern performance diesels. This is a relatively new technology that requires very high pressure fuel injectors which are still a developing technology and weren't available 10 years ago never mind 30. Don't forget mechanical engineering is a much slower moving field than software - they have to design and test things in their field before they release them ;-)
"The weirdest thing about a mind, is that every answer that you find, is the basis of a brand new cliche" -
You've missed the Flex-Fuel. It will run on any variation of ethanol/gas mixture, from E5 all the way up to E100. You decide how green you want to be and this engine will adapt to your choice of fuel.
You are assuming that ethanol is a green fuel. I'm not so sure about corn-based ethanol. Future technology may change that, but I am uneasy using a subsidized food crop to make fuel for cars.
If Slashdot were chemistry it would look like this:Cadaverine
No one outside the USA uses corn for ethanol. It's only grown in the USA because it gets stupidly high government subsidies making it cheaper than everything else. If you drive across France, you'll see lots of bright yellow fields growing rapeseed, which is used to produce fuel.
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Specifically because retarded people weren't able to make the distinction between rape and rapeseed, they call the plant Canola on this side of the pond.
Canola isn't actually rapeseed, it's a crossbreed. Its name comes from Canadian Oil Low Acid. It was developed to have an edible form of rapeseed and now is grown across the world. The Brassica genus includes everything from mustard to rutabega.
I learned to drive in a 2-stroke car -- a 1968 Saab, AFAIK the last 2-stroke car that could legally be sold in the US (50CID was the limit for that year, it was at or a hair under). They are not better in absolute terms, old style 2-strokes are just plain filthy. Their rear mufflers would not rust, instead they would become plugged with a mixture of soot and partially-burned gunk. If you left one of those cars idling for too long next to another car, you would leave an sooty oily spot from the exhaust. You could rejuvenate a muffler, if you had access to a trash fire or bonfire, by cooking it to bake/burn off the gunk.
Using synthetic oil for lubrication helps a little bit, because it is formulated to burn better, but in general, there is no way that these cars were cleaner.
So -- I actually drove one for years, actually worked on their exhaust system, actually left one idling next to another car for too long, and have seen all this with my own eyes. Where did you get your information? I'm curious to know what would cause someone to spout such obvious nonsense with such self-assured authority.
That's only true because they have one ignition event per revolution per cylinder. When you burn gas every revolution rather than every other revolution, you're going to perform more work per unit of displacement, per revolution yes.
But you aren't necessarily going to perform more work per volume of fuel consumed, or more work per volume of pollutants released.
The common 2 stroke engine blows a lot of gasoline (unburned hydrocarbons) out the exhaust, because the exhaust port must, by the nature of the common 2 stroke, be open long after air and fuel is sucked into the engine.
Likewise, they produce foul smelling fumes, because oil must be mixed into the fuel. The common 2 stroke uses the crankcase as a pressure chamber to force air into the cylinder. Because the crankcase cannot be filled with oil, the fuel it's self must lubricate the engine, requiring a mix of oil to be introduced to the gasoline. The result is an engine that smells like a 4 stroke with badly worn out rings and valve guides.
Now, there are a few designs that work around these issues:
Diesel 2 stroke engines use exhaust valves, superchargers, and fuel injection. Because fuel is not injected into the cylinder until long after the intake port and exhaust valves have closed, the engine does not blow unburnt fuel out the exhaust. And because a supercharger is used for exhaust scavenging (removal) the crank case can be filled with oil, eliminating the need for premix. Anyone who's been near a diesel locomotive can attest that it doesn't smell or smoke like your typical 2 stroke.
The same technology can be employed with 2 stroke gasoline engines. Gasoline Direct Injection with supercharging has some clear advantages over traditional 2-strokes... Never-mind the fact that the supercharger could be used to produce some pretty insane power output out of a small displacement engine.
2 strokes also have the advantage that they are quieter than your typical 4 stroke. The only reason people tend to think of them as loud is because they don't require much in the way of silencing.
Anyway... Long rambling post. Short version: no, traditional 2 strokes are not clean. Modern 2 strokes show a lot of promise.
Because diesel is a lot more expensive than gasoline here. Diesel used to be way cheaper tan gas, I don't know what changed to make diesel more expensive. Taxes, maybe?
I'm going to quote a very insightful post I once read. But first, the cliff notes:
1. Diesel is more in-demand in this country than most people think, because there is a very high demand for heating oil in the winter. Heating Oil ~= Diesel with a different dye added.
2. Given a barrel of oil, you can only extract about half as much Diesel fuel as you can regular gasoline. This limits the amount we can supply in-relation to regular gasoline, which is why Diesel (already im high demand) is more expensive.
3. Diesel is more heavily taxed than heating oil or regular gasoline, so in-addition to the fact that diesel is already heavily in-demand, it is the most highly taxed fuel on the road.
So really, the diesel revolution everyone wants to happen in this country is not going to happen. If we had as many Diesel cars as Europe, the fuel prices would go through the roof, because our demand for Diesel/Fuel Oil is already very high.
And now, the quote:
Because the price is set, like all prices in a capitalist economy, by what the market will bear rather than by absolute cost of production. They call this process "market forces," as if they exist outside of themselves, when talking to consumers, but refer to "record profits" when talking to stockholders.
Diesel used to be much cheaper than gasoline, until it became popular to put it into consumer vehicles, but several things have happened to change the production cost of the fuel at the pump.
First is the transition to ultra-low sulfur diesel, which adds perhaps five to eight cents per gallon, counting both direct costs -- the purchase price of low sulfur oil is higher than oil o lesser quality -- and investment costs required to further refine ordinary oil.
The second is taxes. Diesel fuel is essentially the same stuff as heating oil, but is taxed at a higher rate. 18% of the average price at the pump, according to the DOE, is taxes, 54% is the cost of the oil itself, 22% is the cost of refining, and 18% is distribution, marketing, and profit.
Of course many companies sell themselves their own oil, so there may be substantial profit on that transaction as well.
For gasoline, again according to the ODE, 15% of the price is taxes, 55% the cost of the oil, 15% the cost of the refining process, and 14% distribution, marketing, and profit.
In 1990, the average price of gasoline was $1.16 per gallon, the average cost of diesel fuel was $0.73 per gallon, and the average cost of heating fuel was $1.06.
In 2002, the average cost of gasoline was $1.36 per gallon, the average cost of diesel fuel was $0.76 per gallon, and the average cost of heating fuel was $1.13.
1in 2005, the average cost of gasoline was $1.87 per gallon, the average cost of diesel fuel was $1.95 per gallon, and the average cost of heating fuel was $2.05.
As you can easily see, the relative prices have varied all over the map.
The obvious inference is that, despite the higher taxes on diesel fuel in comparison to heating oil, and very similar costs of production, people are more driven to heat their homes than they are to drive their diesel cars, so the companies can charge more.
Likewise, in 1990, diesel cars were uncommon, and the primary users of diesel fuel were commercial, driving large trucks or tractors.
Presumably, a fellow filling up a truck with 300 gallons of diesel fuel every day or two is in a better position to drive a hard bargain than is a fellow filling his VW diesel with 16 gallons one a week or so.
Cheers,
Lee Anne
Man is the animal that laughs.
And occasionally whores for Karma.