Project 1 - Parsing NASA thermodynamic data

AIM:

To write a program in matlab to parse the NASA thermodynamic data file and then calculate the thermodynamic properties of
various gas species.

OBJECTIVE: 

To write a function that extracts the 14 co-efficient and calculates the enthalpy ,entropy and specific heats for all species in the
data file.
Calculating the molecular weight of each species and displaying it in command window.
Plotting cp, enthalpy and entropy for local temperature range specific for each species.
Save the plot as images with appropriate names and dump them in separate folders for each species with suitable name.

INTRODUCTION:

PARSING DATA:

Parsing means to make something understandable. For programming this means to convert information represented in one
form into another form that's easier to work with. This is done by partially analysing the data, understanding its underlying
structure (by making some assumptions based on what you're expecting to see), and then explicitly representing that structure
in the code.
Parsing a file means reading in a data stream of some sort and building an in memory model of the semantic content of that
data. This aims at facilitating perfoming some kind of transformation on the data.

EQUATIONS :-

The equations that we are going to use in the Functions to calculate cp, H,S are

 

Where,
Cp=specific heat
R =molar gas constant
T=temperature
S=Entropy
H=Enthalpy
a=coefficients

BODY OF THE CONTENT:

Code for calling function Specific_heat( ):

function Cp = Specific_heat(a1,a2,a3,a4,a5,a8,a9,a10,a11,a12,T,R,global_midtemp)
%calculating specific_heat for higher and lower temperature respectively
if(T>= global_midtemp)
 Cp=R*(a1+(a2*T)+(a3*(T).^2)+(a4*(T).^3)+(a5*(T).^4));
else
 Cp=R*(a8+(a9*T)+(a10*(T).^2)+(a11*(T).^3)+(a12*(T).^4));
end
end

Code for calling function Enthalpy:-

function H = Enthalpy(a1,a2,a3,a4,a5,a6,a8,a9,a10,a11,a12,a13,T,R,global_midtemp)
%calculating enthalpy for higher and lower temperature respectively
if(T>=global_midtemp)
 
 H=R*((a1*T)+((a2*(T).^2)/2)+((a3*(T).^3)/3)+((a4*(T).^4)/4)+((a5*(T).^5)/5)+a6);
 
else
 H=R*((a8*T)+((a9*(T).^2)/2)+((a10*(T).^3)/3)+((a11*(T).^4)/4)+((a12*(T).^5)/5)+a13);
end
end

Code for calling function Entropy :-

function S=Entropy(a1,a2,a3,a4,a5,a7,a8,a9,a10,a11,a12,a14,T,R,global_midtemp)
%calculating entropy for higher and lower temperature respectively
if(T>= global_midtemp)
 S=R*(a1.*log(T)+(a2*T)+((a3*(T).^2)/2)+((a4*(T).^3)/3)+((a5*(T).^4)/5)+a7);
else
 S=R*(a8.*log(T)+(a9*T)+((a10*(T).^2)/2)+((a11*(T).^3)/3)+((a12*(T).^4)/4));
end
end

Code for calculating molecular weight by calling function wt :-

function Molecular_weight=wt(species_name)
Elements=['H' 'C' 'O' 'N' 'A' 'S'];
Atomic_weight =[1 12 16 14 40 32];
species=upper(species_name)
Molecular_weight=0;
for i=1:length(species)
 for j=1:length(Elements)
 
 if strcmp(species(i),Elements(j))
 
 Molecular_weight=Molecular_weight+Atomic_weight(j);
 k=j;
 
 else
 n=str2double(species(i));
 if (n>1)
 Molecular_weight=Molecular_weight+Atomic_weight(k)*(n-1);
 break
 end

MAIN CODE:

clear all
close all
clc
%R=molar gas constant
R=8.314;
%syntax to open the file THERMO.dat
f1=fopen('THERMO.dat','r')
%To read lines 
l1=fgetl(f1);
l2=fgetl(f1);
value=strsplit(l2,' ');
%To get global temperatures from file in number form
global_lowtemp=str2num(value{2})
global_midtemp=str2num(value{3})
global_hightemp=str2num(value{4})
%temperature range
T=linspace(global_lowtemp,global_hightemp,1000);
%skipping these 3 lines 
l3=fgetl(f1);
l4=fgetl(f1);
l5=fgetl(f1); 
%Reading species ,calcuating cp,h,s and plotting
for i=1:53
 tline=fgetl(f1);
 A=strsplit(tline,' ');
 name_of_species=(A{1});
 lowtemp= str2num(A{end-3});
 midtemp=str2num(A{end-2});
 hightemp=str2num(A{end-1});
 
 %Finding 7 higher coefficients and 7 lower coefficients
 
 tline1=fgetl(f1);
 a=findstr(tline1,'E');
 
 a1=tline1(1:a(1)+3);
 a1=str2num(a1);
 a2=tline1(a(1)+4:a(2)+3);
 a2=str2num(a2);
 a3=tline1(a(2)+4:a(3)+3);
 a3=str2num(a3);
 a4=tline1(a(3)+4:a(4)+3);
 a4=str2num(a4);
 a5=tline1(a(4)+4:a(5)+3);
 a5=str2num(a5);
 
 tline2=fgetl(f1);
 a=findstr(tline2,'E');
 
 a6=tline2(1:a(1)+3);
 a6=str2num(a6);
 a7=tline2(a(1)+4:a(2)+3);
 a7=str2num(a7);
 a8=tline2(a(2)+4:a(3)+3);
 a8=str2num(a8);
 a9=tline2(a(3)+4:a(4)+3);
 a9=str2num(a9); 
 a10=tline2(a(4)+4:a(5)+3);
 a10=str2num(a10);
 
 
 tline3=fgetl(f1);
 a=findstr(tline3,'E')
a11=tline3(1:a(1)+3);
 a11=str2num(a11);
 a12=tline3(a(1)+4:a(2)+3);
 a12=str2num(a12);
 a13=tline3(a(2)+4:a(3)+3);
 a13=str2num(a13);
 a14=tline3(a(3)+4:a(4)+3);
 a14=str2num(a14);
 
 %calculate specific heat(cp),Enthalpy(H),Entropy(S)
 Cp=Specific_heat(a1,a2,a3,a4,a5,a8,a9,a10,a11,a12,T,R,global_midtemp);
 H=Enthalpy(a1,a2,a3,a4,a5,a6,a8,a9,a10,a11,a12,a13,T,R,global_midtemp);
 S=Entropy(a1,a2,a3,a4,a5,a7,a8,a9,a10,a11,a12,a14,T,R,global_midtemp);
 
 %calculating molecular weight and printing it.
 Molecular_weight=wt(name_of_species);
 fprintf('molecular weight of %s= %fn',name_of_species,Molecular_weight);
 
 %PLOTTING CP,H,T
 
cd('C:UsershhhDesktopmatlabNASA FILES')
%creating the folder
mkdir(name_of_species);
cd(name_of_species);
%plotting T vs cp 
figure(1)
plot(T,Cp,'linewidth',5,'color','r')
xlabel('Temperature(T)')
ylabel('Specific heat(cp)')
grid on
title(name_of_species)
saveas(figure(1),'specific heat.jpg');
 
%Plotting T vs H
figure(2)
plot(T,H,'linewidth',5,'color','b')
xlabel('Temperature(T)')
ylabel('Enthalpy(H)')
grid on
title(name_of_species)
saveas(figure(2),'Enthalpy.jpg');
%Plotting T vs S 
figure(3)
plot(T,S,'linewidth',5,'color','y')
xlabel('Temperature(T)')
ylabel('Entropy(S)')
grid on
title(name_of_species)
saveas(figure(3),'Entropy.jpg');
cd('C:UsershhhDocumentsMATLABnasa files')
end