Entropy of superheated steam
Entropy of superheated steam
(OP)
Hello, I am a process engineering student and I need to do some calculations on superheated steam.
I want to calculate entropy for producing steam under specific conditions. I already used the h,s-Diagram and this site: https://www.spiraxsarco.com/resources-and-design-t... to calculate the Entropy. I get the same result every time. For steam at 60 bars gauge, and 365 C I get a entropy value of about 6.4 kJ/kg*K.
But when I do the math with the equations and values from steam tables I always get a value below of 6.2 kJ/kg*K.
I am using these equations: https://www.engineeringenotes.com/thermal-engineer...
With the same values for cp and enthalpy of evaporation as in the calculator.
Why is that, arent the calculators supposed to to exact this thing?
I need to be able to comprehend where the values come from, and 6.4 seems to be right. So what is wrong with the equations.. I hope someone can help me with this I am willing to provide any information.
Best regards,
schniels
I want to calculate entropy for producing steam under specific conditions. I already used the h,s-Diagram and this site: https://www.spiraxsarco.com/resources-and-design-t... to calculate the Entropy. I get the same result every time. For steam at 60 bars gauge, and 365 C I get a entropy value of about 6.4 kJ/kg*K.
But when I do the math with the equations and values from steam tables I always get a value below of 6.2 kJ/kg*K.
I am using these equations: https://www.engineeringenotes.com/thermal-engineer...
With the same values for cp and enthalpy of evaporation as in the calculator.
Why is that, arent the calculators supposed to to exact this thing?
I need to be able to comprehend where the values come from, and 6.4 seems to be right. So what is wrong with the equations.. I hope someone can help me with this I am willing to provide any information.
Best regards,
schniels
RE: Entropy of superheated steam
RE: Entropy of superheated steam
With the equations being an approximation, so relying on the measured values is always the go-to with well researched topics like water.
Thank you really much for your time.