Superheating water injection

Begle1

Begle1

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I have a 1000-1500 PSI water injection line.


Lets say that I coil 10-20 feet of the line inside my downpipe. Or maybe my intake.


Heating the water by a couple hundred degrees would allow me to spray a whole bunch more water, right?
 
Hmmmm...wouldn't the heat expand the molecules and cause less water to be injected...cold water would be like cold air and give a denser charge...but that's just a country boys way of thinking
 
Bad idea. Further more Wet air is LESS dense than dry air.....
 
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I'm talking a liquid here; thermal expansion isn't that much of an issue.

If it's really hot water, then it's going to turn to steam much more readily after it leaves the orifice. And it's the liquid-to-gas phase change that absorbs heat from the intake charge.
 
Begle1 said:
I'm talking a liquid here; thermal expansion isn't that much of an issue.

If it's really hot water, then it's going to turn to steam much more readily after it leaves the orifice. And it's the liquid-to-gas phase change that absorbs heat from the intake charge.
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Then why don't you super heat the fuel so it is closer to combustion point when it is injected?
 
dragnsled said:
Then why don't you super heat the fuel so it is closer to combustion point when it is injected?
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Because the fuel cools the injection pump and injector.

Otherwise I don't think it'd be that bad of an idea, probably not much to gain though...
 
You are not wanting the water to flash to steam as that is not the point. You get results by having the difference in temp between the aircharge and water. The colder the water the more heat it is able to pull from the air.
 
Begle1 said:
Because the fuel cools the injection pump and injector.

Otherwise I don't think it'd be that bad of an idea, probably not much to gain though...
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I think you just need to try some of your theories and post some results:hehe:

From another thread you started...
triton said:
what I know and something I found.....


don't know about flow but, heat excites atoms and causes them to occupy more volume in space. For that reason, the hotter the air is, the thinner it is and why hot air rises. Cold air molecules are packed closer together which is why cold air is more dense. Water vapor also plays a part in density.

When the temperature increases, the higher molecular motion results in an expansion of volume and thus a decrease in density.

moving hot air through a valve would probably be easier since it's thinner
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The same holds true here...the colder the fuel (weather it's diesel,air or water) the more molecules and atoms there are per injection and if I remember correctly you gotta split those atoms to release energy...hence more atoms = more power
 
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Water isn't a fuel, and we're not splitting it apart during water injection. It doesn't absorb energy by splitting apart, it absorbs energy by undergoing a phase change from liquid to gas.

I believe that heating up the water to make it more likely to undergo a phase change, would be in the same vein as heating up a/c refrigerant with a compressor or heating up a nitrous bottle.
 
Begle1 one thing doesn't have anything to do with the other. You heat up a nitrous bottle to push the liquid out of the bottle faster meaning more nitrous. The heating of a/c refrigerant is a side effect of the compression that it undergoes. Then the refrigerant is then cooled while under pressure this way there is more energy to be absorbed during the phase change. With water mist the colder it is the more BTU's/energy it takes to make it phase change. Hence lower intake charge temp's after the injection.
 
Begle1 said:
Water isn't a fuel, and we're not splitting it apart during water injection. It doesn't absorb energy by splitting apart, it absorbs energy by undergoing a phase change from liquid to gas.

I believe that heating up the water to make it more likely to undergo a phase change, would be in the same vein as heating up a/c refrigerant with a compressor or heating up a nitrous bottle.
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Then explain to me what happens when it enters the combustion chamber
 
Begle1 said:
Water isn't a fuel, and we're not splitting it apart during water injection. It doesn't absorb energy by splitting apart, it absorbs energy by undergoing a phase change from liquid to gas.

I believe that heating up the water to make it more likely to undergo a phase change, would be in the same vein as heating up a/c refrigerant with a compressor or heating up a nitrous bottle.
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Dont know how you mess up the theory so bad........the phase change is nothing.........its all the heat to make the change is what counts, you'd be wasting all that heating up your water first......:bang
 
He is studying phase change with the crackpipe, stuff goes from a solid to a liquid to a gas all while absorbing the heat of the flame.
 
Injected water stays as water throughout the combustion process; gaseous water, but still water. Water is one of the main byproducts of combustion; the injected water is just a fraction of the water that comes out the tailpipe.

To change a pound of liquid water 1 degree takes 1 btu; to change a pound of liquid water at 212 degrees to a pound of steam at 212 degrees takes almost 1000 btus.

What's this chart mean to you guys?

graphic5547.png
 
zstroken said:
PUt down the crack pipe and step away from the computer.
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Hey some don't ruin my excuse!


Begle1 said:
Injected water stays as water throughout the combustion process; gaseous water, but still water. Water is one of the main byproducts of combustion; the injected water is just a fraction of the water that comes out the tailpipe.

To change a pound of liquid water 1 degree takes 1 btu; to change a pound of liquid water at 212 degrees to a pound of steam at 212 degrees takes almost 1000 btus.

What's this chart mean to you guys?

graphic5547.png
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Not sure but I want cold water to cool the air charge which in turn lowers EGT's and allows more fuel to be burnt
 
Are we trying to cool the intake charge or are we trying to limit cylinder temperatures?

At 1000 PSI, water boils at 550 degrees. At boost pressure of 40 PSI, it boils at 267 degrees. If it's 550 degrees when all of a sudden it finds itself at 40 PSI, it's going to boil instantly.

Will it drop intake temperatures to below it's boiling point? I don't think so.

But, what will it do when it finds itself in the combustion chamber, still really hot, and still absorbing energy to maintain it's boiling point?
 
The chart means that when I inject water at -479.9999999999F, it 'takes' 1541 BTU of heat out of the air which results in cooler air/denser air/more available air for combustion. You're also not thinking of the air and water mixture reaching a temperature equilibrium.
 
joefarmer said:
The chart means that when I inject water at -479.9999999999F, it 'takes' 1541 BTU of heat out of the air which results in cooler air/denser air/more available air for combustion. You're also not thinking of the air and water mixture reaching a temperature equilibrium.
Click to expand...

I missed that part...someone is dropping ice cubes in their engine
 
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