Quote:
Originally Posted by t vago
Again, this 1700:1 ratio is not a fixed, immutable ratio to be held holy for all time, and it certainly should not be the basis for any reasonable engineering design. It changes due to whatever temperature saturated steam is.
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correct ... and there are no real ideal gases either ... so?
Quote:
Originally Posted by t vago
One other thing: I'm not saying that saturated steam at 212 F is 14.7 psia because it amuses me to do so. I'm saying that saturated steam at 212 is 14.7 psia because this figure is directly out of the steam tables, which were themselves developed during the reign of the steam engine.
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ok ... and? ... I don't get what's the point you are trying to make?
My only guess right now is ... maybe you are indirectly trying to suggest my higher value I got from using the ideal gas law is incorrect ... I am not certain what your point is there???
If the volume is not restricted it expands @212F & 14.7psi by about ~1,700:1 ... but unless I missed something the ideal gas law requires the partial pressure from the steam to go up if you confine the expansion of the same amount of steam in a limited volume ... add more heat energy and you phase transition more liquid water to steam in the fixed volume the steam expansion keeps increasing the pressure ... yes as the pressure goes up so does the phase transition point ... etc ... but if you want to account for that then the final system temperature is not the 212F or 100C you listed either ... it raised with the higher phase transition temperature of the higher pressure the liquid water is under ... which has effects on the available heat energy that can be transferred across the dT difference between the liquid water temp and the initial hot gas temp... etc... etc... like you said we can keep making it more and more complicated if we want to.