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Earth Power Transportation News

50% Efficiency Boost From New Fuel Injection System 379

chudnall notes a Technology Review story on a new gas engine injection system that promises increased efficiency of up to 50%. "The key is heating and pressurizing gasoline before injecting it into the combustion chamber, says Mike Rocke, Transonic's vice president of business development. This puts it into a supercritical state that allows for very fast and clean combustion, which in turn decreases the amount of fuel needed to propel a vehicle. The company also treats the gasoline with a catalyst that 'activates' it, partially oxidizing it to enhance combustion."
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50% Efficiency Boost From New Fuel Injection System

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  • by John Hasler ( 414242 ) on Tuesday March 09, 2010 @09:21AM (#31412382) Homepage
    It is a diesel.

    When is the two-cycle version coming out?
    • by 0100010001010011 ( 652467 ) on Tuesday March 09, 2010 @09:29AM (#31412482)

      Yep, sounds exactly what it is.

      Transonic's injection system varies from direct injection in two ways: it uses supercritical fluids and doesn't require a spark to ignite the fuel. The supercritical fluid mixes quickly with air when it's injected into the cylinder.

      Not sure what is considered 'super critical' but diesel fuel under 180 MPa/26,000 psi is pretty super critical to me.

      Once the fuel is injected into the piston, the heat and pressure are enough to cause the fuel to combust without a spark (similar to what happens in diesel engines), which also helps provide fast, uniform combustion. Ignition can be timed to happen just when the piston is reaching the optimal point, so it can convert as much of the energy in the gasoline into mechanical movement as possible, without wasting energy by heating up the combustion chamber walls, as happens in conventional technologies. The company has developed proprietary software that lets the system adjust the injection precisely depending on the load put on the engine.

      So it sounds exactly like a diesel engine or VW's TSI gasoline engine. []

    • You can run diesel engines on E95, AKA 95% ethanol and 5% gasoline. In one study static compression was raised to 23:1 and timing changes were made, with no other modifications. So this is interesting, in that it's a diesel engine running on gasoline, which has been formerly impossible. But then, it's still an evolution and not a revolution. Also, I'd rather burn diesel.

  • That sounds damned impressive.

    • by mevets ( 322601 )

      I think I'd like to invest in them. If you want, we could put all our money together and stake a more substantial claim in them. I'd be willing to collect.

  • by onion2k ( 203094 ) on Tuesday March 09, 2010 @09:22AM (#31412386) Homepage

    I hate "up to". Anything that claims an improvement of "up to" something is a essentially misleading. You won't get a real world improvement anywhere close.

  • You've just invented direct injection, again.

    • They have added a new twist: They're vaporizing and cracking the fuel before injection. What's being injected is not a liquid fuel mist. It's a hot gas.
  • Let me have some doubts about anything that boasts more than 10% economy. All those fuel saving devices are usually scams.

    I'd like it to be real, but please, have some critical thought before posting a story like this...

    No, didn't RTFA.
    • This isn't a fuel saving device, this is a different engine, with enough different about it, that I believe that there is potential. On the other hand, it is mostly a variant on a Diesel cycle engine (note, I did not say Diesel fuel)- direct injection, with gasoline and no spark.
  • just in time. my mr. fusion is out of beer.
  • magnets? (Score:2, Funny)

    by Gothmolly ( 148874 )

    Also, if you put rare earth magnets on your fuel lines, it streamlines the molecules as they go into the engine.

    • Yeah, I remember on Mythbusters (OK, not the most scientific source, but still), they evaluated stuff like this and (GASP!) found that none of them work. At the end, the remarked it would be hard to see huge increases in fuel efficiency when >98% of the fuel is already burned anyway. Go figure.
    • Also, if you put rare earth magnets on your fuel lines, it streamlines the molecules as they go into the engine

      They were proven to slow down the flow and cluster the explosive molecules around the magnet, slowing the combustion down.

      (the magnet trick is snakeoil.)

  • How much are replacement injectors using this technology going to cost? How much are other various parts going to cost (wiring harness that connects to the injectors, etc.)? How big will the heating and pressurizing mechanism be? (although based on the pic in TFA, it looks like it may piggy back right on the injector...which would raise the cost to replace them by a LOT) How much would that cost to replace? Would it be available only through the OEM company, or will other companies be able to build thei

  • Not a Diesel (Score:4, Informative)

    by Fantom42 ( 174630 ) on Tuesday March 09, 2010 @09:44AM (#31412656)

    People keep saying this is a diesel engine, but it is not. In a diesel engine, the air in the chamber is heated by compresssion up to something hot enough to ignite the fuel. In this design they are heating the fuel and pressurizing it before they inject it into the chamber, so that it turns to vapor as soon as it is injected into the chamber. Someone seemed to be making fun of the term 'supercritical' but that is the word for vapor that has completely transformed from a liquid and has excess internal energy. This is very different from spraying the gas with an atomizer.

    • Re: (Score:3, Informative)

      by Fantom42 ( 174630 )

      Actually, I have the definition of supercritical wrong. I had confounded it with superheated. Supercritical is a substance that is above its critical point, where the liquid and gas phases combine.

      • by vlm ( 69642 )

        Actually, I have the definition of supercritical wrong. I had confounded it with superheated. Supercritical is a substance that is above its critical point, where the liquid and gas phases combine.

        Supercritical temp for toluene is only about 600 degrees F... not a heck of a lot hotter than a kitchen oven. I wonder how hot this thing gets. Your typo may inadvertently be correct. I'm curious how this technology handles different gasoline mixes over time and location. For example, in some states, "old gas magically turns into varnish" but that never happens in Wisconsin, probably because we get a different mix.

        Admittedly I've never heard a good explanation of why, if some brands/mixes of gas magical

  • ...for Transonic. I also installed an HHO system and a 100 mpg carburetor that I built from some 1932 plans along with a tornado action swirl generator in the intake. My mileage and horsepower have improved so much that the car will run 87 mph in 1st gear at idle and gets over 257 mpg. It runs on Burger King bio-diesel.
  • During the first oil crisis, we heard the exact same claims. "Heating the fuel ahead of time gives more miles per gallon". Sure - and more detonation, which is what you get when you ignite ALL the fuel at once. So to suppress detonation, you have to go to higher octane - and higher octane fuels contain more energy, which translates to more mpg. The difference between regular and premium on my car is 5% (yes, I keep track of my mpg on every fill-up - I can tell the difference between the seasons, or when

    • Re: (Score:3, Informative)

      by danbert8 ( 1024253 )

      Umm, you're right about ethanol blending (which is going to become increasingly hard to avoid). Ethanol has a significantly lower energy density of gasoline. Notice that I didn't say regular or premium. Despite your claims of 5% increase in gas mileage, there is no energy density difference between 87 and 92/93 octane fuels. The only thing that octane (and the difference between regular and premium gasoline) is in the knock resistance. If your engine doesn't knock with regular fuel, you gain exactly 0

    • Re: (Score:3, Informative)

      by mcgrew ( 92797 ) *

      The difference between regular and premium on my car is 5%

      be careful using premium fuel, because if the engine is tuned for a lower octaine, running a higher octaine will damage the exhaust valves. Higher octaine burns more slowly (which prevents detonation at higher compression ratios), and too high of an octaine and it's still burning when the exhust valves open. By the same token, too low an octaine and it will knock, damaging the heads, pistons, or (most likely) piston rings.

      A cheaper way to stop spark

  • by nanoakron ( 234907 ) on Tuesday March 09, 2010 @09:53AM (#31412758)

    Does the exhaust also smell like bullshit?

  • Go to Google books and look up a book "Internal combustion", circa 1910.

    In there you'll find the basic equations of IC engine efficiency.

    Clue: They haven't changed a bit since then.

    It all depends on the Carnot cycle, which is basically immutable. A proper gas-air mixture burns at a certain well-defined temperature, and then with expansion, generates a certain amount of work. There's nothing you can do in the way of injection that makes any difference.

    You can come up with minor tweaks, like stratifie

  • NOx and emissions? (Score:3, Interesting)

    by Matt_Bennett ( 79107 ) on Tuesday March 09, 2010 @10:08AM (#31412968) Homepage Journal
    With the increased temperature of ignition, how does this perform with respect to emissions? Since the atmosphere is mostly Nitrogen, and with higher combustion temperature, the greater the NOx. I scanned TFA, but there doesn't seem to be anything on how this technology performs WRT combustion byproducts (by this, I mean beyond CO2 and H20).

    This reminds me of articles in Popular Science during the 70's touting columnist (and notable mechanic) Smokey Yunick and his super efficient engine that also used pre-heating of the intake charge, but I think the technology of fuel injection hadn't moved far enough to get to this level of direct injection.

    • Re: (Score:2, Informative)

      NOx emissions would definitely be an issue if the operation of injection system depends on having a "lean mixture", as the article half-implies. Emission requirements are what killed the 80s concept of a "lean burn" engine. The three-way catalyst required to meet most western emissions regulations, requires a stoichiometric engine, i.e. one that takes in just enough air to oxidise all the fuel, but no more.
  • by sackvillian ( 1476885 ) on Tuesday March 09, 2010 @10:12AM (#31413044)

    This article [] describes a very similar process from a New York company that uses supercritical diesel fuel -- and they report much more sensible efficiency gains of up to 10%. They've only tested in a lab setting so far though.

    I found the article because I was looking for the supercritical points of gasoline, which is a complex mixture of many different hydrocarbons, making the critical points very tricky to estimate. Turns out they are 720K and 60Mpa, from the article above. Their system achieves temperatures this high (almost 400 degrees higher than normal fuel system operations) using exhaust heat. Given that higher temperatures mean improved efficiency, I'd buy the 10% they propose -- though I remain very skeptical abut the 50% proposed in this article.

  • Diesel? (Score:3, Insightful)

    by invisik ( 227250 ) on Tuesday March 09, 2010 @11:20AM (#31413990) Homepage

    I naturally didn't RTFA but it sounds like a diesel to me. Diesel engine already have greater economy from less volatile fuel. The fuel itself isn't heated, the cylinders are heated via glow plugs at start, and then by the combustion itself afterwards. More gas engine should go to direct injection first.

    Or just skip all these "inventions" and keep refining the diesel engine. The latest iteration of the Mercedes diesel is very smooth and incredibly quiet (rivaling gas engines in the same model car) with greater output.


  • by GuyFawkes ( 729054 ) on Tuesday March 09, 2010 @11:36AM (#31414234) Homepage Journal

    As any (mechanical) engineer knows, to get an efficient internal combustion engine you want compression pressures as high as possible and combustion temperatures as high as possible (an oversimplification, to be sure) because an internal combustion engine is a heat engine, and the greater the temperature and pressure difference between the combustion event in the cylinder, and ambient conditions at the end of the exhaust system, the more efficient it is.

    UNFORTUNATELY, some three quarters of the gas that the internal combustion engine draws in from the atmosphere is Nitrogen, and when you expose Nitrogen to the high pressures and temperatures of a combustion chamber, what happens next is simple, and unavoidable, chemistry, you get oxides of nitrogen out the exhaust pipe.

    So on the one hand an efficient engine will be running petrol / gasoline at 13:1 compression ratios, or diesel at 25:1 compression ratios, and polluting the crap out of everything.

    On the other hand, a "green" engine will be running petrol / gasoline at 9:1 compression ratios, or diesel at 17:1, and wasting energy efficiency like an ice rink in Dubai.

    You can't have it both ways.

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