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Stone March 12, 2006 12:50

How to Read Nasa Format
 
How can I read out the nasa coefficients from the nasa thermo build? Does anybody have experiences with it? I want to use them as input for the specific heat capacity.

.. .. .. ..

COEFFICIENTS FOR FITTED THERMODYNAMIC FUNCTIONS

Jet-A(g) McBride,1996. Faith,1971. Gracia-Salcedo,1988. React.

2 g 8/01 C 12.00H 23.00 0.00 0.00 0.00 0 167.31102 -249657.000

273.150 1000.000 7 -2.0 -1.0 0.0 1.0 2.0 3.0 4.0 0.0 0.000

-6.068695590E+05 8.328259590E+03-4.312321270E+01 2.572390455E-01-2.629316040E-04

1.644988940E-07-4.645335140E-11 0.000000000E+00-7.606962760E+04 2.794305937E+02

1000.000 6000.000 7 -2.0 -1.0 0.0 1.0 2.0 3.0 4.0 0.0 0.000

1.858356102E+07-7.677219890E+04 1.419826133E+02-7.437524530E-03 5.856202550E-07

1.223955647E-11-3.149201922E-15 0.000000000E+00 4.221989520E+05-8.986061040E+02

http://cea.grc.nasa.gov/


hagupta March 13, 2006 07:30

Re: How to Read Nasa Format
 
Hi Stone,

I had faced a similar problem some time back. As far as I know, we cannot use the nasa coefficients from the nasa thermo build directly for defining Cp in CFX. The NASA co-efficients which CFX expects us to input are not the same as the one that NASA gives now on the link you have mentioned.

What I had done was created a user-function and entered the Cp at different temp, then created an expression using CEL.

Stone March 13, 2006 12:53

Re: How to Read Nasa Format
 
Thanks for your help hagupta. Can you please explain me how to create an expression from a user-function?

Stone March 13, 2006 13:05

Re: How to Read Nasa Format
 
Ok. I got it by my own.

Stone March 13, 2006 14:35

Re: How to Read Nasa Format
 
Hi hagupta,

the Cp over T plots look fine and seems to be correct. But now I get enthalpy and specific heat capacity for constant volume errors. Any idea? Does something else have to be calculated?

hagupta March 14, 2006 07:44

Re: How to Read Nasa Format
 
>>enthalpy and specific heat capacity for constant volume errors

Where exactly does this error come? What is the error? I assume that you have not selected Constant volume for specific heat type.

Tim March 20, 2006 03:03

Re: How to Read Nasa Format
 
Hi All, I am a bit confused. I supposed I can use that data by translating the format into ccl. Is there any difference in the definition?

Regards Tim


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