Thought experiment

were in agreement that there is a possibility of there being a phasse change though..... from liquid to gas...... and if the droplets are atomized enough, with 1200-1500*F........\


see where im going

Interesting to play around with if you've not seen it before: Not2Fast: Turbo Calculator

--Eric

Kronic, unless our motors are creating electricity in the cylinder, you wount get a molecular split. It take current and polarity to split the 2 so not, it wont have a nitrous effect although nitrous itself isnt an added fuel itself.

ENafziger said:

Interesting to play around with if you've not seen it before: Not2Fast: Turbo Calculator

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I use it often, but remember that it assumes 0% humidity and complete evaporation which are both impossible in the real world. Salt.

Begle1 said:

So if we've established water in the cylinder has no benefit for performance, the next question is:

Does water in the cylinder lower EGT's above and beyond what water in the manifold does? If the small demon doesn't cause any more or less horsepower, does it cause higher or lower EGT's?

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Water in the intake is merely an air condensor. Water in the cylinder = wasted energy (lose a lot of energy getting the water up to those very high combustion temps). So, the additional EGT reduction is generally coming at a performance cost, for said reason.

Going back to the water injection vs a cooler...the difference would be the effectiveness of the cooler (water/air to metal to air heat exchange) vs the effectiveness of the water (water to air exchange).

awenthol said:

Water in the cylinder = wasted energy (lose a lot of energy getting the water up to those very high combustion temps). So, the additional EGT reduction is generally coming at a performance cost, for said reason.

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Please explain why WI does not reduce power (even without methanol). Thanks!

Stygi said:

Please explain why WI does not reduce power (even without methanol). Thanks!

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You're condensing the intake air enough that it out-weighs the additional energy loss in the cylinders (you'd have to compare brayton cycle vs. energy cost of water). That's why there's a fine line at which you are injecting too much water and hurting power.


To add...the specific heat capacity of water is 4.18 J/g°C (air is only 1 J/g°C). So, for a typical performance diesel, let's say we're running 100°F intake air and 1200°F exhaust (which isn't really a fair rep of in-cylinder temp, but I'm just making a point). That means, (including the energy of water vaporization, which you could argue it already is) we're looking at about 5 KJ/g (of energy from the fuel/diesel) to expand/energize the water in the cylinders. Compare this to the 0.6 KJ/g required by air, and you can see the difference.

Going back to Begle1's question...if you had a magic tool that pulled the water back out of the air just before the cylinders, you would see very significant increases in power and efficiency.