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nightkid86
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More power, more fuel effiecient, less emmisions, no cooling system needed.

http://www.autoweek.com/apps/pbcs.dll/article?AID=/20060227/FREE/302270007/1023/THISWEEKSISSUE

4/5/2006 11:32:43 PM

Igor
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it needs to have a radiator and condenser where it would recapture the steam and recycle it. that way it would still carry the extra efficiency with no need to get a tank of distilled water every time you fill up. that's if i understand the concept of its operation correctly

4/5/2006 11:57:37 PM

JBaz
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damn, look at the guy's work shop! looks like a freaking airplane hanger on a ranch? Prolly has an air field too.

4/6/2006 1:05:49 AM

sumfoo1
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yeah i've seen that before pretty neat

4/6/2006 1:27:26 AM

69
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ain't got shit on a carnot engine, in fact nothing does.

4/6/2006 8:12:29 AM

occamsrezr
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Quote :
"it needs to have a radiator and condenser where it would recapture the steam and recycle it. that way it would still carry the extra efficiency with no need to get a tank of distilled water every time you fill up. that's if i understand the concept of its operation correctly"


Yeah, but I think the water/steam gets mixed witht eh fuel/air mixture and would get pretty nasty pretty quick.

4/6/2006 8:24:05 AM

69
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just a add a stripper in the regenerative reheat, or flash it to just below the vapor pressure of the unwanted gasses.

4/6/2006 8:34:38 AM

smoothcrim
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Quote :
"damn, look at the guy's work shop! looks like a freaking airplane hanger on a ranch? "

never heard of crower cams/rods/cranks eh?

4/6/2006 8:37:02 AM

danmangt40
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Igor, the steam goes out the exhaust pipe. The 5th stroke is the steam power stroke, the 6th is the steam exhaust stroke.

so... it's

intake
compression
power
exhaust
---inject water at TDC after exhaust, pop to SHV ---
steam power
steam exhaust

so it takes the heat created in the conventional power stroke that escaped to the cylinder wall
(as opposed to the heat that escapes in the conventional exhaust) and sucks it right back into the cylinder to be carried out with the steam exhaust. Which eliminates the need for a conventional water jacket, supposedly, with the added benefit of making power WITH the heat created , and without spending any more fuel, rather than spending power to get rid of the heat.

It's only a couple steps away from dozens of other things that have been tried. I wrote about this to a pal in japan and he said, "water injection is very old, see WWII airplanes" but those definitely weren't using a completely separate 2-stroke steam cycle tacked onto the end of a conventional 4-stroke.

What's interesting to me is that the prototype is a 1-cylinder, which helps avoid the nasty consequences of the new vibration pattern.

I mean, with two power strokes per every 3 revolutions per cylinder (instead of 1 pwr for every 2 revolutions), that means for a v8 with this 6-stroke design, there's 16 pulses to straighten out in the process of running every cylinder through its cycle, instead of 8, and since the exhaust valve popping open after the steam power stroke will probably sound a little different from how it would after the conventional power stroke, you'd hear probably 3/2x or 2x the firings, but with a more oscillatory sound. So a boring v8, rebuilt for the new cycle, might sound like a v12 or v16 with a lumpy idle. bitchin.



[Edited on April 6, 2006 at 8:58 AM. Reason : either way, it's gonna need a new crank to level out the vibs]

4/6/2006 8:55:39 AM

Nerdchick
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Quote :
"a Crower cycle engine"


I want an engine power cycle named after me

Quote :
"ain't got shit on a carnot engine, in fact nothing does."


Sure Carnot engines are efficient, but they can't realistically be put in cars. Heat transfer at constant temperature is hard to accomplish. The engine has to be either huge or slow, neither of which are really desirable in a car.

4/6/2006 9:00:26 AM

zxappeal
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^you mean the closest approximations to a Carnot engine.

Carnot cycle is theoretically impossible to achieve.

4/6/2006 9:58:23 AM

Igor
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Quote :
"steam goes out the exhaust pipe"


yeah but i figured with a dedicated steam exhaust valve that would only open up during the steam exhaust stroke (while the other exhaust valve is closed) steam could be recycled, cooled, condensed and reused. this may or may not make the power to weight ratio more efficientm but it sure would simplify the refueling process as it would eliminate the need to get distilled water every time

Quote :
"Yeah, but I think the water/steam gets mixed witht eh fuel/air mixture and would get pretty nasty pretty quick."

yes it would require an innovative valve design to prevent this from happening

4/6/2006 10:02:41 AM

zxappeal
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^Cylinder blowby and lubricating oil contamination, along with residual exhaust, would still contaminate the steam.

Here's something else to ponder: there is still an ungodly amount of heat energy lost during the conventional exhaust stroke. A really good design would need to incorporate regeneration/recovery of this heat energy somehow.

4/6/2006 10:34:30 AM

Igor
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allright how about if the "steam exhaust" step used the gasoline instead of water to cool off the engine (no spark during between fifth and sixth cycle). or would the unburned gasoline be bad for emissions? it shouldnt self-combust if the combustion chamber temperature stays relatively low and compression stays reasonable

4/6/2006 10:43:04 AM

69
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there is no exhaust stroke, it recompresses most of the hot gas, and the heat that is lost can be used to preheat the water to saturation temp.

4/6/2006 11:05:02 AM

Aficionado
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Quote :
"Here's something else to ponder: there is still an ungodly amount of heat energy lost during the conventional exhaust stroke. A really good design would need to incorporate regeneration/recovery of this heat energy somehow."


they already have those

they are called turbochargers

4/6/2006 11:20:32 AM

Igor
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i'm no engineer, but i beleive turbochagers use exhaust's kinetic energy, while 69 is talking about thermal (potential?)

[Edited on April 6, 2006 at 12:03 PM. Reason : .]

4/6/2006 11:54:18 AM

zxappeal
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True...turbos do use exhaust's kinetic energy. But think about this here. The hotter a gas is, the more kinetic energy its molecules have. Make sense?

I was thinking more along the lines of high-pressure feedwater heating, as is often done in large-scale boiler applications such as powerplants.

Though turbocharging is definitely a plus here.

[Edited on April 6, 2006 at 12:31 PM. Reason : turbocharging...]

4/6/2006 12:30:33 PM

danmangt40
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zxappeal, google "bmw turbosteamer"

4/6/2006 1:53:12 PM

zxappeal
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The beauty of that system is the ease with which it is incorporated into an existing design...

But I still think that direct cylinder injection of steam/water is possibly more efficient; i.e. more power extracted per amount of fuel burned.

4/6/2006 3:03:25 PM

Prawn Star
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I really like this idea because of it's potential to reduce NOx emissions in diesel engines. NOx, a greenhouse gas, is produced from nitrogen at combustion temperatures. Studies have shown that a moderate drop in cylinder temperatures can reduce NOx emissions by an order of magnitude. Unfortunately power suffers as a result.

4/6/2006 8:50:46 PM

69
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Quote :
"True...turbos do use exhaust's kinetic energy. But think about this here. The hotter a gas is, the more kinetic energy its molecules have. Make sense?"


no, kinetic energy and internal energy are entirely different, first law of thermo:

^U+^H+^KE+^PE=Q+W you can use most of the kinetic energy in a turbine, but it still carries internal energy, or more specifically heat. slowing the velocity of the exhaust gas actually increases the temperature slightly, due to the unused kinetic energy being convertd to internal energy, producing heat. ^S, or entropy can never be negative, and unless the lower heat sink approaches absolute zero, then all the energy "lost" from heat in an internal combustion engine cannot be used to produce work. if heat is not transferred from a high temperate sink to a lower temperature sink, then work cannot be done. therefore in theory, there are two ways to improve overall efficency, reduce the lower heat sink temp, ie the exhaust temp which cannot be lower than the ambient temp, or increase the upper heat sink temp, which is not practical due to metallurgy limitations.

4/6/2006 9:46:01 PM

JBaz
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Quote :
"never heard of crower cams/rods/cranks eh?"

I have, but thats his personal workshop at his ranch. Looks like a mile deep. Would be fun to have all those tools and create stuff.

4/6/2006 10:00:33 PM

bcsawyer
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I don't know about airplane motors, but some tractor engines that burned distillate or kerosene injected water to keep them from spark-knocking because the octane was so low. it didn't have to do with what this guy is doing

4/6/2006 10:09:44 PM

zxappeal
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Quote :
"^S, or entropy can never be negative, and unless the lower heat sink approaches absolute zero, then all the energy "lost" from heat in an internal combustion engine cannot be used to produce work."


...and that would be the second law. No shit. The first law is simply the conservation of energy, and merely states that energy can neither be created nor destroyed. In short, the sum of all energies in a system must equal zero. Energy in equals energy out.

Not even the impossible Carnot cycle, which STILL rejects heat, can produce work from all heat energy.

The kinetic energy you speak of is on a large scale, and is usually a product of a given mass and its velocity. And yes, kinetic enerby and internal energy are different. But we're not really talking primarily about either one here. What is in question is ENTHALPY...H in your conservation equation. And enthalpy (or heat energy) is defined as the sum of internal energy AND the pressure-volume product of a gas. If we consider exhaust to be an ideal gas, and I believe that we can; after all, most of the simpler approximations and modeling of the Otto, Diesel, and Brayton cycles make this assumption, then it follows that the ideal gas law applies: PV = nRT. Furthermore, we can observe that pressure is a direct result of kinetic energy at the molecular level.

You get what I am talking about? You're splitting hairs over trivialities here.

4/7/2006 2:10:07 AM

theDuke866
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my miata had Crower rods


i'm interested to see how this thing turns out...definitely an intriguing idea

4/7/2006 2:24:02 AM

optmusprimer
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blah blah blah

4/7/2006 2:48:25 AM

sumfoo1
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if it worked that well for cooling... that test motor shouldn't look air cooled wouldn't you think?

and no cooling system means when you need heat in the winter... umm.... whatcha gonna do?


slap one of those on the roof?

4/7/2006 7:26:55 AM

danmangt40
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if you read around, you'll find a quote about b. Crower saying that the proto doesn't need the flanges fins, he just didn't bother to remove them. he converted an old diesel 1-cyl to gas or something....

[Edited on April 7, 2006 at 10:25 AM. Reason : airflow=fin, mounting=flange]

4/7/2006 10:24:07 AM

Aficionado
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Quote :
"if it worked that well for cooling... that test motor shouldn't look air cooled wouldn't you think?

and no cooling system means when you need heat in the winter... umm.... whatcha gonna do?"


just run the a/c backwards

4/7/2006 11:48:50 AM

69
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Quote :
"after all, most of the simpler approximations and modeling of the Otto, Diesel, and Brayton cycles make this assumption, then it follows that the ideal gas law applies: PV = nRT. Furthermore, we can observe that pressure is a direct result of kinetic energy at the molecular level."


i forgot exactly what we were talking about, but the pressure is related to molecular interations with the walls of the vessels, but kinetic energy is the the fluid moving as a body, a turbines draw energy from pressure drop, not directly from heat, especially not from a non condensable gas. so the gas on the intake and exit both have nearly the same U, but at different H.

however, this has come up before in a conversation with my thermo professor, and if blade erosion were not an issue, a car turbo would produce more power if saturated water were injected upstream and recondensed in the turbo.

4/7/2006 3:57:17 PM

nightkid86
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electric heat works too, don't have to use coolant to get heat.

Think they could use this in a wankle engine (with more than 3 rotor tips)?

[Edited on April 7, 2006 at 4:43 PM. Reason : s]

4/7/2006 4:42:09 PM

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