Specific heat capacity zero pressure 4th order polynomial for air

badboyz31 · October 2, 2014, 21:24

Hello there, recently I tried to create a model of air based on several data I gathered from the net. But I was unable to find the coefficients for the 4th order polynomial for specific heat capacity.

I tried to enter coefficients based on curve fitting that I did to a table of Cp vs temperature and it turns out that the specific heat ratio in the solver is almost equal to 1 with STP boundary conditions, so I guess that I may have entered the wrong coefficients.

Does someone here actually have the coefficients ? Or where could I find it ?

Thanks in advance.

evcelica · October 3, 2014, 09:40

You have to divide by the gas constant. You also use Cp0 (zero pressure) not Cp.
See the documentation for more details.

badboyz31 · October 5, 2014, 20:11

Alright I'm gonna give it a try.

October 2, 2014, 21:24	Specific heat capacity zero pressure 4th order polynomial for air	#1
badboyz31 Member Join Date: May 2013 Posts: 45 Rep Power: 12	Hello there, recently I tried to create a model of air based on several data I gathered from the net. But I was unable to find the coefficients for the 4th order polynomial for specific heat capacity. I tried to enter coefficients based on curve fitting that I did to a table of Cp vs temperature and it turns out that the specific heat ratio in the solver is almost equal to 1 with STP boundary conditions, so I guess that I may have entered the wrong coefficients. Does someone here actually have the coefficients ? Or where could I find it ? Thanks in advance.

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October 3, 2014, 09:40		#2
evcelica Senior Member Erik Join Date: Feb 2011 Location: Earth (Land portion) Posts: 1,167 Rep Power: 23	You have to divide by the gas constant. You also use Cp0 (zero pressure) not Cp. See the documentation for more details.

October 5, 2014, 20:11		#3
badboyz31 Member Join Date: May 2013 Posts: 45 Rep Power: 12	Alright I'm gonna give it a try.