Ricardo Boosts Ethanol Engine Technology Using GM Motor
These days, more and more research dollars are flowing toward advanced flex-fuel alternatives to diesel engines in attempts to find drivetrains with similar power and fuel economy ratings but smaller displacements, lower costs and cleaner emissions.
Flex-fuel engines are designed to run on gasoline, ethanol or any combination of the two, such as E85, which is 15 percent gasoline and 85 percent ethanol. Several companies are working on variations.
Last year, when diesel fuel carried a 20 percent price premium over regular gasoline – all but eliminating its 20 percent to 25 percent advantage in operating efficiency over gas -- we looked at Ford’s alt engine research efforts with a group of MIT scientists. The two paired to develop a radical new “ethanol boost” twin-fuel turbocharged engine, code-named "Bobcat," that would variably blend gasoline and ethanol on demand to realize diesel-like performance. With such technology, a 5.0-liter engine could potentially produce 500 horsepower and 750 pounds-feet of torque.
Contract engineering firm Ricardo Inc. is the latest company to announce a research breakthrough that’s said to optimize spark ignition engine performance to diesel-like levels of efficiency. Ricardo calls its new engine technology Ethanol Boosted Direct Injection. Its goal is similar or better fuel economy, with the same peak of 660 pounds-feet of torque, found in today’s GM 6.6-liter Duramax V-8 diesel, but from a 3.2-liter flex-fuel V-6.
“We want to create an engine that’s competitive with diesel but without diesel’s substantial costs,” said Rod Beazley, product group director for gasoline at Ricardo. “The engine [we’ve developed] has a much cheaper fuel system and much simpler [exhaust] after-treatment. We also want to take advantage of the positive properties that current flex-fuel engines don’t do.”
It’s taken spark ignition technology decades to catch up to diesel. Diesel is so efficient and powerful because it contains more energy per gallon of fuel than gasoline, and it combusts using compression ignition, which is the tremendous frictional heat generated from the extreme compression of air in the cylinder. Such high temperatures and pressures produce the large amounts of torque that trailer-towers love, but they inhibit thorough mixing of the fuel-air charge in the cylinder, which leads to incomplete fuel burns that produce soot and other pollutants. Conventional gas and flex-fuel engines use spark ignition to detonate the fuel-air mix when the charge is optimally distributed throughout the cylinder chamber. That has two results: The mix burns cleaner, and it burns with less relative power than diesel
Ethanol, however, has a higher octane and heat-of-vaporization point than gasoline, meaning it combusts at a higher temperature and with greater force (higher compression) than gasoline, while also having a greater capacity to cool the fuel/air mix in the cylinder before combustion. This allows a larger charge to be drawn into the cylinder before ignition. This inherent efficiency is what enables a smaller-displacement engine to perform with the same power as a bigger motor if the engine is built to take advantage of it.
Ricardo’s EBDI engine adaptively changes its combustion cycle to match fuel blend and it's built to withstand high compression ratios. This, together with the use of direct injection and turbochargers, makes it almost as efficient as a diesel engine, Ricardo says.
Ricardo has been working on the EBDI engine concept since November 2007 with a number of partner companies.
General Motors supplied Ricardo with its all-new 3.0-liter gasoline direct-injection V-6 as the test engine. The 3.0-liter engine is expected to debut in the 2010 Cadillac SRX and 2010 Chevrolet Equinox crossovers, with power ratings estimated to be 260 hp and 221 pounds-feet of torque.
“The 3.0-liter engine has been highly modified,” said Luke Cruff, chief engineer for the EBDI program at Ricardo. “You might still recognize it from the outside, but we converted it to 3.2 liters so we could get 900 newton-meters [663 pounds-feet] of torque from it. We did this by increasing the [cylinder] stroke plus many other changes. We’re dealing with diesel levels of cylinder pressure in a gasoline-engine packaging environment.”
Other partners collaborating with Ricardo include: Behr (coolers), Bosch (fuel injection system), Delphi (continuously variable valve lift system), GW Castings (engine casting) and Honeywell (turbocharging system).
“Each of our collaborative partners have hit some point during the development of the engine that technically stretches them,” Cruff said. “We’re putting every innovation on the engine to try to find the ultimate fuel economy potential.”
The goal is to place the experimental engine in a GMC Sierra 3500 heavy-duty dual-rear-wheel pickup by the third quarter of 2009.
“We want to have the same vehicle performance, trailer-towing capacity and improved fuel economy in certain drive cycles as the current Duramax 6.6-liter provides today,” Beazley said.
A properly equipped Sierra HD with that configuration can tow up to 16,500 pounds with a fifth-wheel hitch.
The biggest challenge facing Ricardo is not just to achieve the same torque peak as the Duramax, but also to generate lots of torque throughout the engine’s rpm power band while returning similar or better fuel economy because of its small displacement.
“Low-speed torque is important,” Cruff said. “At 1,600 rpm, we’re at 700 nm [516 pounds-feet], at 2,000 rpm we’re at 800 nm [590 pounds-feet], and peak torque is at 3,000 rpm. We have [at least] 70 percent of our max torque from 1,600 rpm all the way up to 5,000 rpm. We’re not going to get market acceptance with a powertrain that doesn’t have the torque capacity that it needs. The challenge then becomes to try to get the [torque] performance out of an engine that’s small enough to still return great fuel-economy numbers. We call this concept extreme downsizing because we’re planning to put a 3.2-liter V-6 spark-ignited engine in a dually one-ton pickup. People kind of look at you funny at first when you tell them about it.”
If Ricardo’s EBDI power expectations prove correct in real-world testing, those funny looks could give way to serious consideration by future truck buyers.
Comments
I loved my 6.0litre F250 engine w/ the programer. 600#ft, measured torque IS A BEAST!! I don't care how you get there, gas or other... The 17.5mpg was great, too. I just won't pay, again, the premium for A) diesel fuel cost & B) the mfg'r price premium for the "diesel package"! Gitter-done boys!! Oh... I want 30mpg, so sneek some kind of hybrid for men in there too...
If this works just think what GM / Ricardo could do to Audi in automobile endurance racing!!! I hope this works but I am still skeptical about ethanol as a fuel source for a miriad of reasons. When we are out of town ( my wife and I live in the Houston, tx. area) we always get much better fuel economy with the smaller town fuel mix because it doesn't have any ethanol at all in it. We have noticed that we have much better pedal response as well with the country mix. Sombody tell folks to FORGET ABOUT HYBRIDS, they suck and they will have huge enviornmental impacts when the batteries start coming out.
As everyone seems to forget, batteries are 100% recycleable and DO NOT end up in land fills unless irresponsible people put them there.
George: You are getting lower mileage with the ethanol mix because you are using ethanol in an engine designed to run on gasoline. Engines are specifically designed these days, some high performance cars will run very poorly on anything but premium. By the same token, ethanol is inefficiently used in gasoline engines, so everyone with a flex-fuel car or using an ethanol blend gets poorer mileage.
Race cars - about the only engines built to run ethanol or methanol - get HUGE amounts of power from small engines, so the BTU argument does not hold up. Using some of the same principles racers have used for decades, smaller engines, with smaller fuel demands, can be built for alcohol fuels, with power outputs exceeding similar size gas engines.
The efficiency of a diesel, the smoothness of gas engines, with a fuel that drops in price as demand for it increases.
[Adaptation of new technology to market, Blackmon]
So some one has an idea to build a gas engine that will run diesel engine compression? Am I missing something here? Seems to me that is a handgranade waiting to explode. Top fuel dragsters come to mind. How is building an engine on the verge of exploding going to do anyone any good. Just so it can run more effiecently on ethonal. That and other articles on the web seem to state the case clearly that even if all the cars and trucks produce from here on out were E85 compatable, the american farmer could not produce the stock needed to wean us off petroleum. Not to mention E85 is a blend. 100 percent bio-diesel is a start in the right direction and looks like we can make it out of pond scum. That means we can cook it indoors in high rise farms and not take up valuable land for food production.
You get fewer MPG's on E85 because it requires a higher ethanol to air ratio to run than what is required with gasoline. These experimental engines only get better mpg because they are smaller.
A 3.2L Ethanol engine can get about the same mpg as a 6.6L Diesel (doesn't sound so good now does it). Now of coarse that's if it's naturally aspirated... Put a turbo on it and you can get the power of the 6.6L and MPG of the 6.6L. That is in an unloaded setting (ie cruising on level ground unloaded). Put a trailer behind yourself and try pulling through rolling hills with that turbo spun up and you'll get worse MPG than you would've got from the 6.6L.
Ethanol is a great fuel don't get me wrong but it isn't a replacement for diesel and it won't even replace gasoline if your objective is fuel economy.
That's why Ford is researching the dual fuel "Bobcat", they are trying to mitigate the loss of fuel economy with ethanol by only using it when the extra power is needed. To the extent they can shrink the engine without decreasing power out put they maybe able to recognize a net gain in fuel economy, but it will still be no substitute to diesel for towing.
"with a fuel that drops in price as demand for it increases."
I can't believe I missed that... wtf are you smoking? Even leaving out the clear lack of understanding of basic economic principles... I guess you missed the rise in price of corn last year cause by ethanol subsidies. You know where everyone got mad at the US for pushing up food prices in the 3rd world? Am I the only one that ever watches the new anymore?
@Enjelus and @Shawn: Would now be a good time to let you both know I'm headed over to Ricardo in the morning to see this engine in person? :-)
Mike, have fun looking at the engine. I hope their test mule is also up and running for you to take a spin in. Heck if they build one in a 3/4 ton 4X4 and drop in a gooseneck ball, bring it over and I'll real world test it for them at the farm. However they need to ship me the E85 also as we only have one tank on the farm and that has diesel in it. Concept is nice but just the economics are hard. Make a great deal for Joe Average in the sedan, but as farmers I don't think we are ready to buy all new equipment that is untested in the field.
Plus, could you clarify for me or get Ricardo too. I was browsing their website and came across a chart. It looked to be a comparison between running an engine on E40, E85, straight gas and diesel. If I read it right and I think I did, E85 actually performed worse than E40 or diesel. So I hope I did read something wrong there. Have fun!
You read that right, price of ethanol will drop as demand increases. As the demand increases refineries will produce newer more efiicient way to produce ethanol. Currently today we are migrating away from corn based ethanol and producing mass quantities of cellulosic ethanol which is cost effective and has a positive net energy. A large majority of refineries are now using this methood and actually costs much less than corn based. All those leaves you toss to the curb in the fall, and those bags of grass clippings, cardboard, paper and other wastes are now being cheaply converted into ethanol. So as you can see as the demand increases more refineries will resort to this methood which could reduce costs greatly. Some of the cost comes from the final process of ethanol, when the ethanol is dried. This sucks all the water out of ethanol so that it can be blended with gasoline. Although all refineries do this it is an un-needed step because ethanol can be blended with gasoline in its hydrated (distilled only) form. Soon enough this will come into play in the industry. This greatly reduces energy input using hydrus ethanol, possibly up to half the cost. E-85 in the united states is used because of cold starting problems in cold enviornments. This fuel has around 105 octane, where hydrous ethanol can have up to 120 octane. The main point that im reaching at is that ethanol is a perfect fuel to replace gasoline As people have said above, yes you get less mileage with ethanol but it can be improved as follows. Say you have a 3.5 liter gas only, flex engine, that pushes 300 horsepower and gets 30 miles per gallon. A high compression E-85 optimized engine could be around 3.0 or 2.8 liter engine, which is smaller producing 300 or more horsepower with the same 30 miles per gallon because of the lower displacement. Finally an engine optimized for hydrous ethanol could be 2.2 litrs pushing 300 or more horsepower with the same 30 mpg. These are just esimatins, the exact numbers could be more or less than my given values. But as you see as long as ethanol is optimized it is far superior than gasoline. Just like gasoline is optimized in your gas car, an ethanol optimized engine would outperform and get better or the same mileage with ethanol. The best part about ethanol is that its not toxic, if a tanker acidently spills 100 billion gallons of ethanol in the ocean, there will be barely any to no impact on the enviornment. Ethanol is highly biodegratable and hydroscopic.
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