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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.
Name...That...Autocomplete!
Various theories hint at the interests of the oil lobby to continue four-stroke dominance (just look at the low mpg of most american manufacturers in general) and perceived customer comfort being the most widely used trump. High fuel efficiency does not usually provide sporty acceleration, low engine noise, and high torque at low revs.
That being said, no doubt many consumers don't care as much about that as the marketing departments of the automotive industry. In reality, noisy diesels have sold well in Europe (thanks in part to diesel fuel subsidies) and customers have bought poor performing, smaller cars for everyday use. They just don't make big margins on cars that sell for less than €8000 new. So once again striking a balance between shareholder interest (increasing profits) and global economic / ecological interest (decreasing emissions and oil reliance both by better fuel efficiency and better combustion of cleaner, more varied fuel) is an impossible mission.
Until oil prices go up, don't expect any good technology to prevail. The four stroke petrol engine will die, but not before oil costs increase.
Conversion Rate Optimisation French / English consultant
They can be run on multiple fuels (or indeed, mixtures thereof) and would be ideal for a series-hybrid vehicle, where the drivetrain could be eliminated (it was the weak point in the turbine cars.)
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
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.
Repeal the 17th Amendment TODAY! Also Please Read http://www.gnu.org/philosophy/right-to-read.html
Euro & Japanese manufacturers are less influenced by the US fuel lobby. Explain why petrol costs way less in the US : (the answer is taxation in Europe). The taxation strategy indirectly subsidises (it's not quite a subsidy, of course, but to the end user making one fuel cheaper than the other is akin to subsidy even if the difference is the level of taxation)
Agree in part with behaviour patterns in Europe, but I've seen roads from Fort Worth & surroundings to Dallas clogged with large vehicles mostly used for a less than 20 mile daily commute...
Conversion Rate Optimisation French / English consultant
Something like 50-60% of new cars sold in Europe for the last few years are diesel. Nobody seems to see a problem with them.
nb. This figure applies to luxury cars (Mercedes, BMW, etc) as well. The rich people aren't seeing a problem either (in fact diesels are very good for long-haul highway driving).
Diesel engines would be a far better match than gasoline for American tastes (ie. lots of torque at low revs), I can't imagine why they don't use them.
No sig today...
"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.
I don't know what technical marvels they implemented to get 168mpg.
From my understanding, it'd be set up like the huge ship based two stroke diesels. You utilize a turbocharger and direct injection into the cylinder. That way you're not blowing gas/oil out with the exhaust. You can control precisely how much and when fuel is introduced into the chambers.
Then you end up with an engine that's almost half the weight for the power. Cooling needs can even be reduced because you can use the air during the flush phase to help cool the engine.
I don't read AC A human right
Cars, choosing them is one of the areas where decisions of people are being extremely influenced by perceptions and urban myths.
You know your extremely visible purchase will be witnessed by many people, you might want them to look at it in particular (depending on the area) way. Also, since it's a non-trivial expense, you rationalize your choices excessively. All this creates quite complex behaviors.
One that hath name thou can not otter
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.
I am TheRaven on Soylent News
So where is this magical Ford engine at now? A one-off prototype car is no better than a single experimental engine.
Oh, please, isn't the location obvious? It's sitting in the "high-priority" warehouse, right next to the Ark of the Covenant and the Roswell "balloon debris"...
We'll get to it, in 30 years, 8 months, 4 depressions, 12 corruptions, and 20 trillion dollars in oil profits from now...
Until then, YMMV...
People tend to buy for worst-case instead of average-case scenarios - just in case they ever take that holiday to Disneyland, they don't want to pack in to a compact. Europeans on the other hand take a train.
What on earth are you talking about? You can't just make retarded, unsupported statements like that! We Europeans are quite fond of our cars, and have no problem packing a family of four into a typical European/Asian family car for vacation. if you think you need to drive a Hummer or a 2-ton pickup truck to get where you're going, then perhaps you should learn to pack your stuff with some common sense (and perhaps put your all-American family on a diet).
Yes, that diet comment assumed a very clique image of Americans. I allowed myself this small freedom, as you seem to have no problem making stupid statements and assumptions about us.
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.
FYI, soot is not the only emission to look out for, NOx emissions of a diesel are the other headache. The Issue is that you can directly trade NOx emissions for Soot emissions visa/versa simply by changing the injection timing, while making the same power. Soot I don't believe is a green house gas, and is more of a local air quality item. So any manufacture can make a very clean diesel engine that makes no soot, NOx be dammed, IE European standard. So that is what you saw, starting after 2000 manufactures eliminated the soot. Then in 2008 NOx was the driving regulation in USA, so they brought back the soot, and added in Soot filters to capture that out of the exhaust and burn it later.
Also The amount you refine petroleum the reduced energy content, but also the cleaner burning. So diesel is less refined, and thus has more energy content, but wasn't as clean of burning. So now we refine it more, make it cleaner burning at a cost.
I have lived in Europe and the US - people in Europe really have a hard time understanding the American way of driving. Every winter we (family of 4, plus dog) take a trip of 2000 miles round trip, and most summers we take another of 1000 miles. A 400 mile round trip camping trip is something we do twice a year. No way am I going to rent a van 4+ times a year, I love my minivan and all its creature comforts.
Look at the statistics - Americans have almost twice as many cars per head as in Europe, and they drive each of those cars almost twice as far each year. The fact that we get our fuel "almost for free" may not justify such behavior, but it does help explain it.
I think that a lot of Europeans kid themselves that their virtuous behavior is due to a moral superiority when really, if fuel suddenly cost one third of what it does now in Norway, I'd predict in a couple of years you'd be seeing a lot of V8s on your roads.
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.
What? I guess it depends how you define efficiency but for equivalent rotations of the output shaft a Wankel engine sweeps twice it's measured volume compared to 4 stroke 4 pot, that's why they have appalling mpg, they're small but they definitely not efficient.
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.