Dryness fraction - is anything missing here ?

[rmenon]

dryness fraction - is anything missing here ??

Hi Guys,
Got a couple of questions I need answers on.
a)A closed vessel of 0.8 m3 capacity contains dry saturated steam at 350 kPa. The vessel is cooled until the pressure is 200 kPa. Calculate
1) mass of steam in the vessel
2) final dryness fraction

b)A steam plant that operates on the ideal Rankine Cycle produces steam that is dry and saturated at 500 kPa. The condenser pressure is 20 kPa. Calculate the dryness fraction at the turbine exhaust (expansion is isentropic)
What is the work done per kilogram of steam ?

Thanks and regards
Raj

 

[Andrew Mason]

Hi Guys,
Got a couple of questions I need answers on.
a)A closed vessel of 0.8 m3 capacity contains dry saturated steam at 350 kPa. The vessel is cooled until the pressure is 200 kPa. Calculate
1) mass of steam in the vessel
2) final dryness fraction

Can you determine the temperature of the steam in a)? Hint: the word "saturated" is important.

AM

 

[rmenon]

Do you mean from steam tables

 

[Andrew Mason]

Do you mean from steam tables

Well, you could boil water at 350 kpa and see what temperature it boils at. Or you could just look it up in a steam table.

AM