Transonic Supercritical Fuel Injection is another technical advancement for the internal combustion engine that shows rather startling gains in efficiency, 50 to 75 percent! “A test vehicle the size and weight of a Toyota Prius (but without hybrid propulsion) showed 64 miles per gallon for highway driving.” That beats the hybrid. Transonic Combustion, the company working on this, has a test vehicle in the lab that is getting 98 mpg running at a steady 50 mph.
“A supercritical fluid is basically a fourth state of matter that’s part way between a gas and liquid,†said Michael Frick, Vice President for Engineering. A substance goes supercritical when it is heated beyond a certain thermodynamic critical point so that it refuses to liquefy no matter how much pressure is applied.
The injection systems can be integrated into modern high compression engines which means manufacturers don’t need to develop entirely new drivetrains.
In laboratory tests on modern engine architectures, our technology has successfully run on gasoline, diesel, biodiesel, heptane, ethanol, and vegetable oil. Recently our engineers achieved seamless operation switching from several different fuels on one of our customer’s engines
TSCi Fuel Injection achieves lean combustion and super efficiency by running gasoline, diesel, and advanced bio-renewable fuels on modern diesel engine architectures. Supercritical fluids have unusual physical properties that Transonic is harnessing for internal combustion engine efficiency. Supercritical fuel injection facilitates short ignition delay and fast combustion, precisely controls the combustion that minimizes crevice burn and partial combustion near the cylinder walls, and prevents droplet diffusion burn.
The supercritical fuel mixes very rapidly with the intake air which allows better control of the location and timing of the combustion process. This system allows extremely lean combustion (up to 80:1 air-to-fuel ratios at cruise) extracting far more energy from any given amount of fuel, you get much higher mileage and lower emissions, too.
Every time we see a new electric drivetrain, along comes a dramatic improvement in the internal combustion engine. This isn’t something you’ll be able to hook up to some 50 year old engine, but it shows the modern ICE still has amazing opportunities for improvement. Very cool.
Link: SAE
Link: Transonic Combustion
Link: Next Big Future
lostinoz says
“A substance goes supercritical when it is heated beyond a certain thermodynamic critical point so that it refuses to liquefy no matter how much pressure is applied.”
Yeah, I’m not too excited to have this on a motorcycle, no matter how efficient it may end up being, There’s something about super heated flammable steam between my legs I’d prefer to deal without.
Interesting technology however, I’d like to see this on the street.
masonv45 says
lostinoz,
You already have a small gas fire immediately below a 3 gallon tank of gas…
Both technologies have the same potential for damage to the rider.
bkowal says
Hmmmm.. sounds suspiciously like a high-tech version of the “100 MPG†carburetor. There is only so much energy in gasoline (or any fuel). In order to get a 50% – 75% increase in efficiency, you would need to extract that much more energy from the same amount of fuel. Where is the extra energy coming from?
lostinoz says
Masonv45,
while i agree with that line of thinking, its not super heated steam, if i break a fuel line it will leak, it will get uncomfortable, if i shut off the fuel it will reduce the chances of blowing up.
if i break a STEAM LINE between my legs.. well… that old lady from mcdonalds aint got nothing on me.
Spartandude says
I saw this about 10 years ago with someone running the fuel circuit just under the valve seat in the head. Your volume of super critical fuel will be so small that you will have more danger from your exhaust pipe that if all of the super critical fluid suddenly burst out at you.
@ bkowal: standard diesel is actually pretty efficient, but a good engine still only gets about 40% energy conversion and the rest is lost. By leaning out the mixture that drastically the cycle efficiency could easily be bumped up. This is not free energy, just less waste.
I like the tech and need to dig up that old hot rod magazine article. Oh, wait Hurricane Ike was in my garage; that collection is no more. Sigh. Maybe I can find it online.
fast eddie says
Been there done that my lawn mower was heating gasoline in the sixties
the technology lies in the refining of the fuel { cartel, lobby, etc. } less urathane, more
petoleum figures don’t lie , liers don’t figure 14.35:1 the tanks hold the mix related
to this math as soon as inquiring minds figure this out we all can get out there and ride
Tip; for unlimited M P G , on grades over 5 % longer than 1/4 Mi. use you kill button
shut your engine off and coast . Shure is fun to read tough , ice racing is fun but
cold . I just want to ride come on spring Kneeslider keep up the good work F.E.
bkowal says
Spartandude, if this system is not extracting “free energy” than the best it could do is run as a practical lean-burn engine which would reduce pumping loses (like a diesel).
This would not provide anywhere near 50% to 75% improvement.
Tim says
I think you are missing the point. The pressure allows for much less fuel to be wasted. In a new, fuel injected, internal combustion engine, there is excess fuel injected into the cylinder. That is partly why my Speed Triple has air injectors and a catalytic converter. It is also why it can run nearly 13:1 compression ratio. The flame doesn’t burn as long with this supercritical injection, but it burns more completely. So, instead of dumping fuel overboard, you burn it.
If you really want to understand the process, I recommend following the link to the SAE.
Tim
Tin Man 2 says
The ICE is far from dead, The improvements just keep coming! The Energy density in a Gallon of Gas far exceeds any Battery, If you can control waste, the 50% gain is very feasible.
Patrick says
Spartantude, I too remember the engine you mention. The guy who built it ran pressured gasoline through a channel adjacent to the exhaust valve seat to heat it. From there it went to holes in the intake valve seat; when the intake opened, it affected quasi-timed, fuel injection.
Al says
Hurray for science!
Tim says
Or, if you prefer, you can read this from Wikipedia:
..”supercritical fluid is any substance at a temperature and pressure above its critical point. It can diffuse through solids like a gas, and dissolve materials like a liquid. In addition, close to the critical point, small changes in pressure or temperature result in large changes in density, allowing many properties of a supercritical fluid to be “fine-tuned”. Supercritical fluids are suitable as a substitute for organic solvents in a range of industrial and laboratory processes. Carbon dioxide and water are the most commonly used supercritical fluids, being used for decaffeination and power generation, respectively.”
and
“In addition, there is no surface tension in a supercritical fluid, as there is no liquid/gas phase boundary. By changing the pressure and temperature of the fluid, the properties can be “tuned†to be more liquid- or more gas-like. One of the most important properties is the solubility of material in the fluid. Solubility in a supercritical fluid tends to increase with density of the fluid (at constant temperature). Since density increases with pressure, solubility tends to increase with pressure. The relationship with temperature is a little more complicated. At constant density, solubility will increase with temperature. However, close to the critical point, the density can drop sharply with a slight increase in temperature. Therefore, close to the critical temperature, solubility often drops with increasing temperature, then rises again.[2]
All supercritical fluids are completely miscible with each other so for a mixture a single phase can be guaranteed if the critical point of the mixture is exceeded. The critical point of a binary mixture can be estimated as the arithmetic mean of the critical temperatures and pressures of the two components,
Tc(mix) = (mole fraction A) x TcA + (mole fraction B) x TcB.
For greater accuracy, the critical point can be calculated using equations of state, such as the Peng Robinson, or group contribution methods. Other properties, such as density, can also be calculated using equations of state.[3]”
I think the other important item is the effect of brake mean effective pressure on the process. As you probably know, BHP=(BMEP x RPM x Displacement (Cubic Inches))/792,000. If you can increase brake mean effective pressure, in theory, you produce more downward force on the piston. By the nature of the supercritical fluid, pressure is significantly higer.
It is also “no surface tension.” This means that combustion is much more complete.
There is no free energy, just an alteration of the combustion medium.
Tim
Tim says
BTW Spartandude, was this what you’re looking for?
http://www.hotrod.com/techarticles/hrdp_0401_torque_horsepower_guide/equations_relationships.html
Jim Flower says
Back around ’85, Hot Rod Magazine ran an interview with Smokey Yunick. Smokey had developed what he called the “Hot Air Engine”, using exhaust heat to pe-heat the intake charge on an Iron Duke 4-cylinder engine. The performance and efficiancy was outstanding.
The common thread here is superior atomization via heat. That is why it is compatible with diverse fuels. An indicator of efficient combustion is the reduced ignition lead time; the better the burn, the less time it takes. My gas dragster, a 109″ V-twin at 15 to 1 compresion runs best at only 21 degrees timing; and that’s on slow-burning 118 octane racing gasoline.
Imagine disassembling your engine and finding no carbon, anywhere.
Cool tech…
Jim
http://www.jimflowerllc.com
Kirill says
This is cool technology. I see the same problem as with other improvements that get more power: stress. I would assume u need more expensive components to run higher compression ratio; exponentially more expensive. If i remember correctly, that is the same problem that was with an engine that ran on gas and water (6 cycles). it was on kneeslider earlier
–Kirill
Spartandude says
@ Tim: No I think it is the one Patrick was mentioning (by the way that’s not Patrick of Motorcycles Unlimited is it?).
bkowal, “…the best it could do is run as a practical lean-burn engine which would reduce pumping loses (like a diesel).
This would not provide anywhere near 50% to 75% improvement.”
It looks like they are using a direct injection, compression detonation set up (diesel), but comparing it to a spark ignition ICEs (which are routinely as inefficient at 18% in the combustion fuel energy conversion). From their site:
“50% or more for automotive engines (relative to spark-ignition engines dominating the road today in the U.S.) and 25% or more for heavy-duty truck engines (relative to today’s diesel truck engines)” http://www.tscombustion.com/autoinefficiency.html
So the values don’t appear to be outside the realm of reality. The other problem is that these values are usually inflated to the best case theoretical improvement. Reality should show a decent increase in efficiency, but I would also bet not the 75%.
I could just as easily say that a 2010 VW golf diesel is 1% to 20,000% more efficient than my 1995 Dodge Ram 1500, but without the further details of the vehicle type, what part of the range given and what efficiency value you are looking at it would be a useless fact even if it is completely correct.
Steve says
Google smokey yunick adiabatic engine. Lots to read.I always wondered what became of the whole concept.
Spartandude says
Steve, yup that’s him. Smokey Yunik. Thank you.
http://schou.dk/hvce/
Jim Flower says
Great link, Spartandude, that was exactly what I was refering to.
Guys like Smokey are a rare breed.
Jim
bkowal says
There are theoretical limits to the efficiency of any heat engine (Carnot Cycle), no fancy fuel injector is going to change that. Wiki says its around 37% for typical engines.
Most modern engines are very good at getting complete combustion, the catalytic convertor just cleans up a little of the mess due to sudden changes engine load/speed/tempurature that real engines see.
So where is the extra energy coming from?
More Details:
http://en.wikipedia.org/wiki/Internal_combustion_engine#Energy_efficiency
Spartandude says
bkowal: look up the carnot cycle. The efficency is given by:
E=1-Tc/Th
If you look at the engine described you will find that the Tc is the same for each iteration. However the Th is drastically increased locally by leaning out the air fuel mixture and gets around the wiki sited problem by containing the combustion event into the localized area. This increase is one reason this may not get off the ground. The EPA does not like diesel engines as much since the higher Th leads to elevated emissions of oxides of nitrogen. There are engineering controls to reduce these oxides, but not very easy and does reduce the efficiency of the system. The ratio of efficiency compared to the Carnot cycle should not change much between these engines, but the Th is probably where your “free” energy comes from.
“Wiki says its around 37% for typical engines” No the wiki says “Most steel engines have a thermodynamic limit of 37%” So if you take a base line of 18% and bump that up by the stated 50% then you get 27% (18*1.5), which is no where near the thermodynamic limit. Also the engines calculated efficiency will probably be derived from the perfectly tuned state of the engine and not from the actual real world efficiency. Most people don’t operate in the ideal efficiency of their engines since there are always trade offs for power band, desired performance and the HP bragging.
37% efficiency is good for ICE Diesel and almost unheard of for spark ignition.
Spartandude says
I should have read a bit more:
“Even when aided with turbochargers and stock efficiency aids, most engines retain an average efficiency of about 18%-20%”
Same wiki page.
WRXr says
If it sounds too good to be true…it is.
James says
WRXr, it does not sound too good to be true, just too good to be affordable……
coho says
Just because it’s not perfect already doesn’t mean it’s not a really good idea.
WRXr says
I’m not saying it isn’t a good idea. maybe it is. But it sounds more like marketing than science. Even the name “Transonic Supercritical Fuel Injection” sounds more like science fiction than something you would find in an engine. Why not ” Ultra-Vorpal Matrix Fuel Injection” or ” Mr. Fusion”?
Zippy says
Good thing is we still have plenty of oil left to burn. There were over 200 major finds last year. Over 1 trillion barrels waiting to be pumped and refined.
And if you were at the flat track last night in Daytona you were begging for some global warming!!
Spartandude says
‘Why not †Ultra-Vorpal Matrix Fuel Injection‒-WRXr
That is awesome. I am saving that one.
Actually most of their site seems to be a big marketing display. In this free market economy the winner isn’t always the one with the best tech, it also hinges strongly on the PR departments skill, market share, public perception, and a fair bit of luck. So they are just doing their job a little too well for our personal tastes.
Now if any of us actually commanded enough unassigned assets to be attractive to a start up like this I am sure they could hook us up directly with the engineering group to get around the PR BS and get the closer to reality information.
Joek Hondius says
To good to be true.
If this were true it would change the world.
Forget about alternative energy sources!
The site and the way the tell the story sound
too much like other extremely promising hypes.
No more 160HP litre bike, but a 160HP 250cc!
With 4 times the MPG and 1/4th the harmfull gasses.
I’d get one.
Nick56289 says
Joek Hondius
……..50% to 75% more efficient does not mean 4 times the power, 4 times the MPG and a quarter of the emissions
Kai says
So this wonderous new thing injects a pressurised stream of fuel directly into the combustion chamber?
Maybe I’m wrong but I think we’ve been doing this for decades :p
Miles says
Kai, no that isn’t what we have been doing for decades, it is hot enough to change its properties noticeably.
Some things to note:
Less octane is better(!)
Run at extremely lean ratios
Cannot form droplets in cylinder.
Plan is to burn the fuel away from the combustion chamber surfaces, keeping them cooler and cleaner.
Interesting idea, I hope it gets some uptake.
Paul says
Zippy, I assume you were being sarcastic. Those 200 major finds in 2009 amounted to about 10 billion barrels, problem is, we used 20 billion barrels.
L.K. says
I think the claims of increased efficiency come from the cruise scenario – essentially it takes very little power to maintain 50mph so why would you put in all the fuel needed to control detonation if detonation were not a factor – if, from a fueling perspective, you can use as much fuel as needed to produce the minimal power needed to maintain cruise without having to worry about negative consequences to your engine, then you have increased efficiency, right?
This is why diesels run more efficient at cruise, the detonation is needed for ignition, so if your power requirement is low, you only put in enough fuel to keep that level of power… this kind of sounds like that except that the fuel is no longer just directly injected into the engine via a sophisticated atomizer, but instead the physical properties of the fuel are altered somewhat (somehow) to allow even leaner burn without wrecking the engine – you’re not getting any more power out of the fuel, you’re just using the absolute minimum necessary for a particular power requirement.
Kai says
Temperature goes up with pressure – current diesel fuels can go upwards of 800 degrees with current pressure ‘standards’.
Presumably this article is talking about temperatures ten times that? I’ve read studies from ten years ago where tests were being done with up to three times that temperature.
So far Diesel walks a tight-rope, looking for better efficiency and burn through higher pressure and temperature, but correspondingly higher pollutants – balancing nox, soot, etc, it’s almost like you can’t win…
sean says
One advantage of the lean-burn capability is that you can have the throttle
more open at all power levels short of maximum – you aren’t using less fuel,
but you burn it with more air. That means less energy lost sucking air past
a butterfly valve, and more MPG.