Project 1 - Parsing NASA thermodynamic data

Aim: To extract all the coefficients of the given thermodynamic data and to calculate the different parameters like Entropy, Enthalpy and Specific Heat with respect to Temperature and also to calculate molecular mass of different species mentioned in the given file.

Theory: Parsing in computer languages refers to syntactic analysis of the input code into its components parts in order to facilitate the writing of compilers and interpreters. It can be used to describe split or separation.

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 performing some kind of transformation on the data.

Formula used:

For Specific Heat: `c_p=R*(C1+C2*T+C3*T^2+C4*T^3+C5*T^4 )`

For Enthalpy:`: H=R*T*(C1+C2*T/2+C3*T^2/3+C4*T^3/4+C5*T^4/5+(C6)/T)`

For Entropy:`S=R*(C1LnT+C2*T+C3*T^3/2+C4*T^3/3+C5*T^4/4+C7)`

Steps:

1. Initially open and read the file using the ‘fopen’ command and then use the ‘fgetl’ command to read the data line by line.
2. Since, first three lines are comment lines. Hence, we should use the ‘fgetl’ command on all the three lines to read it as a comment line.
3. Now we will use the ‘str2num’ command to convert a string scalar or character array to a numeric matrix.
4. Now we will use ‘for’ loop to run the command 53 times to get the required data of different species. In this we will also use ‘str2find’ command to search the string inside another string.
5. ‘str2num’ command is used again and again from C1 to C14 to convert a string scalar to a numeric matrix so that it can be used to find the coefficients.
6. Now we will use ‘mkdir’ command for creating a folder for the species we will get as output.
7. Now we will use ‘linspace’ command for the temperature ranges from 300 to 2000 K using in 200 divisions.
8. Now we will calculate the properties like Enthalpy, Entropy and Species using the given formulae. At first we will use the ‘for’ loop to define the range from 1 to temperature divisions which is 200.
9. Now we will use ‘if else’ statement to calculate the properties if temperature<3000 and if its not then else statement.
10. In this step we will plot the different species for Enthalpy against Temperature, Entropy against Temperature and Specific Heat against Temperature.
11. Now we will save each and every file in the directory using the ‘saveas’ command and at last ‘cd’ command to display the current folder.
12. After that we will use the function ‘Molecular_mass’ to run all the species.
13. Finally we will use the ‘fclose’ command to close the specified file.

MATLAB Code:

function MM = molecular_mass(species_name)
species = upper(species_name);
element = ['H', 'C', 'N', 'O', 'A'];% Name of the elements
atomic_wt = [1.00794 12.0107 14.0067 15.9994 39.948];%Molecular mass of elements
MM = 0;%Initialize
for i=1:length(species)
for j=1:length(element)
if strcmp(species(i),element(j))
MM = MM + atomic_wt(j);
u = j;
end
end
n = str2num(species(i));
if n>1
MM = MM + atomic_wt(u)*(n-1);
end
end
end

close all
clear all
clc


%Opening & Reading of file
file = fopen('THERMO.dat','r')


%Reading of line
l1 = fgetl(file)


%Global temperature values
l2 = fgetl(file)


%Comment Lines
comm_1 = fgetl(file)
comm_2 = fgetl(file)
comm_3 = fgetl(file)
A = strsplit(l2,' ');

%Global Temperature
Global_low_temp = str2num(A{2})
Global_mid_temp = str2num(A{3})
Global_high_temp = str2num(A{4})


%Species
for i=1:53
species= fgetl(file);
species_name = species(1:6)
L_1 = fgetl(file);
L1 = strfind(L_1,'E');
C1 = str2num(L_1(1:(L1(1)+3)));
C2 = str2num(L_1((L1(1)+4):(L1(2)+3)));
C3 = str2num(L_1((L1(2)+4):(L1(3)+3)));
C4 = str2num(L_1((L1(3)+4):(L1(4)+3)));
C5 = str2num(L_1((L1(4)+4):(L1(5)+3)));



L_2 = fgetl(file);
L2 = strfind(L_2,'E');
C6 = str2num(L_2(1:(L2(1)+3)));
C7 = str2num(L_2((L2(1)+4):(L2(2)+3)));
C8 = str2num(L_2((L2(2)+4):(L2(3)+3)));
C9 = str2num(L_2((L2(3)+4):(L2(4)+3)));
C10 = str2num(L_2((L2(4)+4):(L2(5)+3)));



L_3 = fgetl(file);
L3 = strfind(L_3,'E');
C11 = str2num(L_3(1:(L3(1)+3)));
C12 = str2num(L_3((L3(1)+4):(L3(2)+3)));
C13 = str2num(L_3((L3(2)+4):(L3(3)+3)));
C14 = str2num(L_3((L3(3)+4):(L3(4)+3)));



%Creating folder for species
mkdir(['C:\Program Files\MATLAB\R2016a\bin\',species_name]);


%Temperature Range(in K)
Temp = linspace(300,5000,200);


%Universal gas constant(In KJ/KgK)
R = 8.314;


%Calculation of Properties
for j = 1:length(Temp)
if Temp(j)<3000
Cp = (C1+C2.*Temp+C3.*Temp.^2+C4.*Temp.^3+C5.*Temp.^4).*R;
H = (C1+(C2.*Temp)./2+(C3.*Temp.^2)/3+(C4.*Temp.^3)/4+(C5.*Temp.^4/5)+C6./Temp).*Temp.*R;
S = (C1*log(Temp)+C2.*Temp+(C3.*Temp.^2)/2+(C4.*Temp.^3)/3+(C5.*Temp.^4)/4+C7).*R;

else
Cp = (C8+C9.*Temp+C10.*Temp.^2+C11.*Temp.^3+C12.*Temp.^4).*R;
H = (C8+(C9.*Temp)/2+(C10.*Temp.^2)/3+(C11.*Temp.^3)/4+(C12.*Temp.^4/5)+C13./Temp).*Temp.*R;
S = (C8.*log(Temp)+C9.*Temp+(C10.*Temp.^2)/2+(C11.*Temp.^3)/3+(C12.*Temp.^4)/4+C14).*R;

end
end


%plotting


%Temperature vs Entropy
figure(1)
plot(Temp,S,'linewidth',3,'color','b')
title(species_name)
xlabel('Temperature')
ylabel('Entropy')


%Temperature vs Enthalpy
figure(2)
plot(Temp,H,'linewidth',3,'color','k')
title(species_name)
xlabel('Temperature')
ylabel('Enthalpy')


%Temperature vs Specific heat
figure(3)
plot(Temp,Cp,'linewidth',3,'color','y')
title(species_name)
xlabel('Temperature')
ylabel('Specific heat')
directory = (['C:\Program Files\MATLAB\R2016a\bin\',species_name]);  
cd(directory)



%Saving the File
saveas(1,'Entropy.jpg');
saveas(2,'Enthalpy.jpg');
saveas(3,'Specific heat.jpg');
cd('C:\Program Files\MATLAB\R2016a\bin\') 

MM = molecular_mass(species_name)
end
fclose(file)

Result:

Comment Line:

Molecular Weight Of Different Species:

Sample Plots:

C

Enthalpy vs. Temperature

Entropy vs. Temperature

Specific Heat vs. Temperature

H

Enthalpy vs. Temperature

Entropy vs. Temperature

Specific Heat vs. Temperature

Errors or Warnings: