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Reading thermodynamic data

IdealGases.jl uses the NASA-9 polynomials to calculate the thermodynamic properties ($c_p, h, s$)

IdealGases.readThermo — Function
readThermo(filename)

Reads a NASA 9 polynomial thermo definintion file which can be obtained from NASA thermobuild and returns a dictionary of species.

See here for typical data format

Usage: If a NASA 9 polynomial definition file thermo.inp exists then,

spec = readThermo("thermo.inp")

will return a dictionary of species.

readThermo only considers 2 temperature ranges (typically 200-1000 K and 1000-6000 K) but more can be added if needed.

source

Default species included

A number of species of interest are included in IdealGases.jl.

["Ar", "H2", "CO2", "H2O", "N2", "O2", "Air", "CH4", "C2H5OH", "C2H4", "C2H6", "C3H8", "C4H10,n-butan", "C4H10,isobuta", "C5H12,n-penta", "C5H12,i-penta", "C8H18,n-octan", "C8H18,isoocta", "NH3", "Jet-A(g)"]

Adding new species

Any new gaseous species can be added for calculations by adding the NASA-9 polynomial data to the thermo.inp file. For example, if you wanted to add methane (this already exists in the database so you don't need to):

  • Step 1: Go to the thermobuild.
  • Step 2: Copy the data for the species of interest
   CH4               Gurvich,1991 pt1 p44 pt2 p36.                                 
 2 g 8/99 C   1.00H   4.00    0.00    0.00    0.00 0   16.0424600     -74600.000
    200.000   1000.0007 -2.0 -1.0  0.0  1.0  2.0  3.0  4.0  0.0        10016.202
-1.766850998D+05 2.786181020D+03-1.202577850D+01 3.917619290D-02-3.619054430D-05
 2.026853043D-08-4.976705490D-12                -2.331314360D+04 8.904322750D+01
   1000.000   6000.0007 -2.0 -1.0  0.0  1.0  2.0  3.0  4.0  0.0        10016.202
 3.730042760D+06-1.383501485D+04 2.049107091D+01-1.961974759D-03 4.727313040D-07
-3.728814690D-11 1.623737207D-15                 7.532066910D+04-1.219124889D+02
  • Step 3: Append this to thermo.inp