Project 1 - Parsing NASA thermodynamic data

AIM: TO PARSE THE THERMODYNAMIC DATA FROM NASA USING MATLAB

THEORY: The official record of thermodynamic values at different temperatures has been stored by NASA in the form of polynomials with specified constants ranging from one to fourteen for various species. In order to quantify the values, the polynomials can be solved with defined temperature values in accordance with our requirements.

The term ‘parsing’ refers to MATLAB reading an m-file (script or function) and translating it into an internal code that it stores in memory. It is this ‘parsed’ file in memory that is actually run when you execute the code.

· SPECIFIC HEAT –

C_P/R=a1+a2×T+a3×T^2+a4×T^3+a5×T^4CP​/R=a1+a2×T+a3×T2+a4×T3+a5×T4

· ENTHALPY –

H/RT= a1+a2×T/2+a3×T^2/3+a4×T^3/4+a5×T^4/5+a6/TH/RT=a1+a2×T/2+a3×T2/3+a4×T3/4+a5×T4/5+a6/T

· ENTROPY –

S/R=a1×logT+a2×T+a3×T^2/2+a4×T^3/3+a5×T^4/4+a7S/R=a1×lnT+a2×T+a3×T2/2+a4×T3/3+a5×T4/4+a7

where,

CP = Specific Heat

H = Enthalpy

S = Entropy

R = Universal Gas Constant (8.314 J/mol.K)

T = Temperature

* The First 7 Coefficients are High Temperature Coefficients and the Second 7 Coefficients are Low Temperature Coefficients.

To write a function extracting the 14 coefficients from the data file and calculating the specific heat, enthalpy and entropy of all species.

To calculate molecular weight of every species and displaying in command window.

To plot specific heat, enthalpy and entropy with temperature range distributed from global high temperature to global low temperature.

To create a separate folder for all the plots and saving them in ‘.png’ format.

function [cp, h, s]=coeff(a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,T)
R=8.314;
for j=1:length(T)
if T(j)< 300


cp=(a1+a2.*T+a3.*T.^2+a4.*T.^3+a5.*T.^4).*R;
h=(a1+(a2.*T)./2+(a3.*T.^2)./3+(a4.*T.^3)./4+(a5.*T.^4)./5+(a6./T)).*R.*T;
s=(a1.*log(T)+a2.*T+(a3.*T.^2)./2+(a4.*T.^3)./3+(a5.*T.^4)./4+a7).*R;


else
cp=(a8+a9.*T+a10.*T.^2+a11.*T.^3+a12.*T.^4).*R;
h=(a8+(a9.*T)./2+(a10.*T.^2)./3+(a11.*T.^3)./4+(a12.*T.^4)./5+(a13./T)).*R.*T;
s=(a8.*log(T)+a9.*T+(a10.*T.^2)./2+(a11.*T.^3)./3+(a12.*T.^4)./4+a14).*R;

end
end

matlab main code:

clear all
close all
clc


%to determind the thermodynamic data file
f1=fopen('THERMO.dat','r');
for i=1:5
fgetl(f1);

end

for i=1:53
file_name=fgetl(f1)

t=strsplit(file_name,' ')


%to determind species
species_name=t{1};

q=length(t)
% to determind temp
low_temp=str2double(t{q-3})
high_temp=str2double(t{q-2})
mid_temp=str2double(t{q-4})

 

line_2=fgetl(f1)
l2=strfind(line_2,'E');
a1=str2double(line_2(1:(l2(1)+3)));
a2=str2double(line_2((l2(1)+4):(l2(2)+3)));
a3=str2double(line_2((l2(2)+4):(l2(3)+3)));
a4=str2double(line_2((l2(3)+4):(l2(4)+3)));
a5=str2double(line_2((l2(4)+4):(l2(5)+3)));

% extratig coefficiet from second line
line_3=fgetl(f1);
l3=strfind(line_3,'E');
a6=str2double(line_3(1:(l3(1)+3)));
a7=str2double(line_3((l3(1)+4):(l3(2)+3)));
a8=str2double(line_3((l3(2)+4):(l3(3)+3)));
a9=str2double(line_3((l3(3)+4):(l3(4)+3)));
a10=str2double(line_3((l3(4)+4):(l3(5)+3)));


% extratig coefficiet from third line

line_4=fgetl(f1);
l4=strfind(line_4,'E');
a11=str2double(line_4(1:(l4(1)+3)));
a12=str2double(line_4((l4(1)+4):(l4(2)+3)));
a13=str2double(line_4((l4(2)+4):(l4(3)+3)));
a14=str2double(line_4((l4(3)+4):(l4(4)+3)));

% create a folder 'species' to save thrmo plot of species
mkdir(['C:\Users\sarath\Desktop\New folder (2)\',species_name]);
cd(['C:\Users\sarath\Desktop\New folder (2)\',species_name]);


T=linspace(low_temp,high_temp,500);

% calling func

[cp,h,s]=coeff(a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,T);
%plottig

% plot bt temp and specific heat
figure(1)
plot(T,cp,'linewidth',3,'color','b')
title(species_name)
xlabel('temperature')
ylabel('specific heat')

%plot bt temp & enthalpy
figure(2)
plot(T,h,'linewidth',3,'color','b')
title(species_name)
xlabel('temperature')
ylabel('enthalpy')

%plot bt temp & entropy

figure(3)
plot(T,s,'linewidth',3,'color','b')
title(species_name)
xlabel('temperature')
ylabel('entropy')


%saving plots

saveas(1,'specific heat.png')
saveas(2,'enthalpy.png')
saveas(3,'entropyn.png')


end

 

calculating molecular weight of species code :

%molecular_mass 
species = species_name;
elements = ['H','C','O','N','A'];
atomic_weight = [1 12 14 16 40];

%Calculating Molecular Mass for the different species.
mol_mass = 0;
for i = 1:length(species);
  for m = 1:length(elements);
     if strcmpi(species(i),elements(m)); %Here it check if both charcter string has same value
       mol_mass = mol_mass + atomic_weight(m);
       position = m;
     end
  end
end
 n = str2num(species(i));
 if n > 1
  mol_mass = mol_mass + (atomic_weight(position)*(n-1));
 end

fprintf('Molecular Weight of %s:%f\n',species,mol_mass)

output: species location

plots:

for:o

for:N

for:CH2CHO

conclusion: the parsing of thermodynamic data file by nasa is done using certain command in MATLAB.function that extracts the 14 co-efficients and calculates the enthalpy, entropy and specific heats for all the species in the data file are ploted and saved in seperate folder screen shot has been attached and some of the plot also attracted as a photo form abow.Calculate the molecular weight of each species and display it in the command window.