Property Tables Question [Thermodynamics]

AI Thread Summary
To find the specific enthalpy (h) for a superheated vapor at a pressure of 700 KPa and specific entropy of 7.6953 KJ/(K Kg), the values of s_f and s_g from Table A.5 indicate the state is superheated. The closest pressures in the tables are 0.6 MPa and 0.8 MPa, necessitating interpolation between these values. To perform this interpolation, the corresponding enthalpy values (h1 and h2) must be calculated, which requires determining the temperature (T) of the state. Understanding how to navigate the superheated steam tables is essential for completing the calculations. Proper use of these tables will yield the required specific enthalpy.
AfterSunShine
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Homework Statement


Given
Pressure=P=700 KPa
Specific Entropy = s = 7.6953 KJ / ( K Kg )

Find the Specific Enthalpy (h)

Homework Equations


No equation
Am using the property tables at the end of the following book :
Thermodynamics, an engineering approach, by Yunus A. Cengel and Michaek A.Boles 7th edition.


The Attempt at a Solution


By obtaining the values of s_f and s_g from Table A.5 and compare it to s, the state is Superheated Vapor.
This means I will use Table A.6
The pressure = 700 KPa = 0.7 MPa
But the most closest pressure to this pressure is 0.6 MPa and 0.8 MPa
So I will use interpolation like that
P (MPa) h
0.6 h1
0.7 h
0.8 h2

h1 and h2 must be calculated in order to apply interpolation to find h
To find h1,h2 Need to know T of the state
But I do not how to find it

Help please.
 
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Look up double interpolation.
 
I did not get it :\
 
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AfterSunShine said:

Homework Statement


Given
Pressure=P=700 KPa
Specific Entropy = s = 7.6953 KJ / ( K Kg )

Find the Specific Enthalpy (h)

Homework Equations


No equation
Am using the property tables at the end of the following book :
Thermodynamics, an engineering approach, by Yunus A. Cengel and Michaek A.Boles 7th edition.



The Attempt at a Solution


By obtaining the values of s_f and s_g from Table A.5 and compare it to s, the state is Superheated Vapor.
This means I will use Table A.6
The pressure = 700 KPa = 0.7 MPa
But the most closest pressure to this pressure is 0.6 MPa and 0.8 MPa
So I will use interpolation like that
P (MPa) h
0.6 h1
0.7 h
0.8 h2

h1 and h2 must be calculated in order to apply interpolation to find h
To find h1,h2 Need to know T of the state
But I do not how to find it

Help please.

If p and s are known, the state is known totally, including sp. enthalpy h and temperature T. Just need to know how to use your (superheated) steam tables.
 
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