Dieselgman, if say for instance I was pulling 2500 watts from the CD and this load slowed it down to 48 hz from the nominal unloaded 51.5 hz and adding water then put it up to 49 hz then this would show an increase in power, I do know that when running on load on high compression changing over to low compression raises the hz irrespective of the fuel rack position, this is infinately repeatable and works both ways, up and down, I assume its because of the increased power produced on low compression setting. This is is reversal of what happens when you apply more load to an engine which is operating at near its rated output. Its easy to lock the rack off and try it this with a fixed fuel amount.
Glort, for a given volume in a combustion chamber, replacing a percentage of the air charge with water droplets, vapour, or non combustible jellybabies
will reduce the available energy produced by the expansion of fuel burning in that space, cooling the air charge prior to it entering the cylinder will give more oxygen per unit volume and increase power but how much this will be offset by the water used to cool it being unable to burn, is anyones guess.
As far as I know simple power in a diesel is dictated by the MEP (mean effective pressure) which is the difference between the compression pressure at ignition and the average pressure throughout the power stroke, having said all this, diesels do operate with excess air so there may be a bit of space for some water in there.
Good to discuss this with you.
Mark.