Quote:
Originally Posted by IamIan
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???
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What exactly is this expansion ratio for water at 212 F? 1700:1?
I certainly don't think so.
The specific volume of liquid water at 212 F is 0.016715 ft^3 per lbm.
The specific volume of saturated steam at 212 F is 26.80 ft^3 per lbm.
Divide the specific volume of steam at 212 F by the specific volume of liquid water at 212 F, and you get... wait for it... 1603.35.
That's right! 1603.35:1, not 1700:1! You're willing to continue this discussion on the basis of a rule-of-thumb figure that was not even meant for any sort of engineering at all.
Quote:
Originally Posted by IamIan
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
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Yah, you did miss something. I just addressed part of it, but here's the other part.
Unless there's work done on that gas after the steam is added to it, the system presented in this example will only have saturated steam. How can it possibly be otherwise? 99.9% of the water in the final system is still a liquid! And if the liquid water and the steam are at the same temperature, which must happen due to conservation of energy because no outside heat was added apart from injection of water at 100 C, and due to the fact that no compression work was performed on the system from the outside, how could there possibly be more steam added?