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Originally Posted by drmiller100
again, I don't care about one gram of exhaust gas.
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You should. That exhaust gas provides the necessary medium for carrying the heat energy needed to vaporize water in your spiffy little imaginary engine.
Quote:
Originally Posted by drmiller100
so I went to a kpa to psi conversion thingy, and it says 22064 kpa is 3200 psi.
that seems like a lot to me.
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Well, water is a strange animal. Above 373 C and 22064 kPa, it's not really purely a gas nor purely a liquid.
Quote:
Originally Posted by drmiller100
It seems like if I could put a bit of water in, and limit the temperature to a MAXIMUM of 373, I would not have any Nox, and have some decent pressure to drive the piston down.
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Liquid water does not just magically turn into a gas. If it did, people would not be able to survive near a stovetop that had a boiling pot of water on it. All that boiling water expanding 1700 times in volume or so in an instant, you know.
Quote:
Originally Posted by drmiller100
It also seems like if the max combustion temp was 373, I might lose less to the piston and cylinder walls (delta T and all that.)
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Do you understand that liquid water takes a lot of heat energy out of exhaust gas in order to change from a liquid into a vapor? Do you understand that said process will cool off the gas in question, and will lower its pressure as a result?
Because it sure seems like you keep ignoring these basic facts.
Quote:
Originally Posted by drmiller100
Is it possible combustion temps rise above 373 C?
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Well, seeing as how combustion temperatures can range anywhere between 5500 C and 10000 C, inside a firing cylinder on its combustion stroke, I'd say that was pretty possible.
Here's something else that just came to mind: You do realize that you need a pressure differential to inject water into a vessel that's at 150 psia, right? In other words, how are you going to pressurize water to be above 150 psia, so that it'd squirt into your engine? How much power would you need to do this? How are you going to prevent 1200 to 2500 psia burning charge from leaking into your water injection mechanism?