Property Tables Question [Thermodynamics]

In summary, the specific enthalpy (h) can be found by using Table A.6 from the book Thermodynamics, an engineering approach by Yunus A. Cengel and Michael A. Boles 7th edition. The pressure (P) and specific entropy (s) are given as 700 kPa and 7.6953 kJ/(K kg) respectively. By comparing s to the values of s_f and s_g from Table A.5, it can be determined that the state is superheated vapor. Using interpolation with the nearest pressures of 0.6 MPa and 0.8 MPa, the specific enthalpy can be found.
  • #1
AfterSunShine
27
3

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.
 
Physics news on Phys.org
  • #2
Look up double interpolation.
 
  • #3
I did not get it :\
 
  • #4
Did not get what? Look it up on Google.
 
  • #5
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.
 

What are property tables in thermodynamics?

Property tables in thermodynamics are a tool used to organize and present thermodynamic properties of substances such as temperature, pressure, volume, and internal energy. They are often used to calculate values for thermodynamic processes and are commonly available for gases, liquids, and solids.

How are property tables used in thermodynamics?

Property tables are used in thermodynamics to obtain information about a substance at various states, such as its temperature, pressure, and internal energy. These values can then be used in thermodynamic equations to calculate other properties or to analyze a thermodynamic process.

What types of properties are typically included in property tables?

Property tables usually include properties such as temperature, pressure, volume, internal energy, enthalpy, entropy, and specific heat. These properties may vary depending on the type of substance and the specific table being used.

How are property tables organized?

Property tables are typically organized in a tabular format, with columns for different properties and rows for different states of the substance. The values in the table are usually obtained through experimental data or calculations based on thermodynamic equations.

Are property tables accurate?

Property tables are considered to be accurate for most practical purposes, but they may not be exact due to limitations in the underlying data and assumptions made in the calculations. It is important to use the correct table for the specific substance and conditions being studied and to understand any limitations or uncertainties associated with the table.

Similar threads

  • Engineering and Comp Sci Homework Help
Replies
2
Views
2K
  • Engineering and Comp Sci Homework Help
Replies
10
Views
1K
  • Engineering and Comp Sci Homework Help
Replies
1
Views
7K
  • Engineering and Comp Sci Homework Help
Replies
8
Views
3K
  • Engineering and Comp Sci Homework Help
Replies
4
Views
3K
  • Engineering and Comp Sci Homework Help
Replies
4
Views
2K
  • Engineering and Comp Sci Homework Help
Replies
3
Views
5K
  • Engineering and Comp Sci Homework Help
Replies
9
Views
2K
  • Engineering and Comp Sci Homework Help
Replies
1
Views
6K
  • Engineering and Comp Sci Homework Help
Replies
5
Views
3K
Back
Top