Mike Rapoport wrote:
Water injection does not increase efficiency, it lowers it. The water goes
in as a liquid and goes out as a gas. The energy to do that comes from
burning fuel.

Same thing is true of a steam engine. In a steam engine it is
the phase-change of the water that makes it possible to convert
the heat from burning fuel into mechanical energy.

It will always take more fuel to produce a given amount of
power with water injection than without. Water injection
does allow higher
MP or higher compression so the engine can produce more power.

The thermodynamic efficiency of a heat engine is a function of the
compression ratio. Increasing the compression ratio increases
the efficiency. That is not to say that with water injection
there are not also increased losses that negate that advantage,
but the fact remains that increased compression ratio, absent
other factors, increases efficiency.

Piston
engine fighters used it for more peak horsepower and some turbines use it
for the same purpose but it definately come at the price of higher fuel burn
per horsepower.


Ok, I believe you.

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FF