Project 1 - Parsing NASA thermodynamic data

FILE PARSING

AIM:

To write a MATLAB code for file parsing the NASA thermodynamic data file and to extract fourteen coefficients thermodynamic properties like Cp, H and S, for all the species in the data file. And then to find out the molecular mass of each species and finally to plot a graph for enthalpy, entropy and Cp with respect to temperature.

THEORY:

FILE PARSING: File parsing is defined to deals with the field of computational linguistics where it commonly defines the natural language processing. Natural language processing (NLP) is nothing but concerned with programming the computers to process and analyse the human written language.

ENTHALPY (H): Enthalpy is defined as the kind of energy. It is the sum of internal energy and flows energy. It is denoted by symbol H.

ENTROPY (S): Entropy is defined as the property and it is the measurement of the randomness of molecules. It is denoted by symbol S.

SPECIFIC HEAT (CP): Specific heat is nothing but it is the amount of heat per unit mass required to raise the temperature by one degree Celsius.

MOLECULAR WEIGHT: molecular weight, also called molecular mass, mass of a molecule of a substance based on 12 as the atomic weight of carbon-12. It is calculated in practice by summing the atomic weights of the atoms making up the substance's molecular formula.

Molecular weight = (Number of atoms) * (Atomic weight), where we calculate the molecular weight of all species.

FORMULAS USED:

Below the formulas are used to calculate the enthalpy, entropy and specific heat.

ENTHALPY FUNCTION CODE:

% challenge 8 - NASA file parsing Enthalpy Function calculation
% Code


function [H] = enthalpy(x1,x2,x3,x4,x5,x6,x8,x9,x10,x11,x12,x13,temp,lmt,const_R)
if temp<=lmt
    H = (x8+(x9*(temp/2))+(x10*(temp.^2/3))+(x11*(temp.^3/4))+(x12*(temp.^4/5))+(x13./temp)).*temp*const_R;
else
    H =   (x1+(x2*(temp/2))+(x3*(temp.^2/3))+(x4*(temp.^3/4))+(x5*(temp.^4/5))+(x6./temp)).*temp*const_R;
end
end

ENTROPY FUNCTION CODE:

% challenge 8 - NASA file parsing Entropy Function calculation
% Code


function [S] = entropy(x1,x2,x3,x4,x5,x7,x8,x9,x10,x11,x12,x14,temp,lmt,const_R)
if temp>=lmt
    S = (x1*log(temp)+x2*temp+x3*(temp.^2/2)+x4*(temp.^3/3)+x5*(temp.^4/4)+x7)*const_R;
else
    S =   (x8*log(temp)+x9*temp+(x10*(temp.^2)/2)+(x11*(temp.^3)/3)+(x12*(temp.^4)/4)+x14)*const_R;
end
end

SPECIFIC HEAT FUNCTION CODE:

% challenge 8 - NASA file parsing Specific Heat Function calculation
% Code


function [cp] = specific_heat(x1,x2,x3,x4,x5,x8,x9,x10,x11,x12,temp,lmt,const_R)
if temp<=lmt
    cp = (x8+(x9*temp)+(x10*temp.^2)+(x11*temp.^3)+(x12*temp.^4))*const_R;
else
    cp =   (x1+(x2*temp)+(x3*temp.^2)+(x4*temp.^3)+(x5*temp.^4))*const_R;
end
end

MOLECULAR WEIGHT FUCTION CODE:

% challenge 8 - NASA file parsing molecular weight Function calculation
% Code

function Mole_wt = mol_wt(species_name)
weight = 0;
elements = ['H','C','N','O','Ar'];
mass = [1.0,29.36,52.37,14.008,15.78,45.63];

for i = 1:length(species_name)
    for j = 1:length(elements)
        if strcmpi(species_name(i),elements(j))
            weight = weight+mass(j);
            y = j;
        end
    end

    number = str2double(species_name(i));
    if(number>1)
        weight = weight+(mass(y)*(number-1));
    end
    Mole_wt = weight;
end

MAIN CODE:

% PROJECT - 1 // PARSING NASA THERMODYNAMIC DATA USING MATLAB

clear all
close all
clc

% Opening the file 
f1 = fopen('THERMO.dat','r');
% using for loop to read first 5 lines
for i = 1:5
    %fgetl reads each 5 line from a file
   a = fgetl(f1);
end

for i = 1:53
    % Getting first header line which is a character with different data's
   header_line =  fgetl(f1);
   % Splitting the string based on delimiter
   % Our delimiter is space
   a = strsplit(header_line,' ');

   % We use curly brackets because it is character
   % 1st cell represents the species_name
   species_name = a{1};
   % Local lower, medium, higher temperatures, we are converting string to number
   llt = str2double(a{end-3});
   lmt = str2double(a{end-1});
   lht = str2double(a{end-2});
   T = linspace(llt,lht,500);

   % Getting species with exponential coeifficent
   line1 = fgetl(f1);
   % Finding the location of exponent(E) for line 1
   e1 = strfind(line1,'E');
   % We are converting string to number
   a1 = str2double(line1(1:e1(1)+3));
   a2 = str2double(line1(e1(1)+4:e1(2)+3));
   a3 = str2double(line1(e1(2)+4:e1(3)+3));
   a4 = str2double(line1(e1(3)+4:e1(4)+3));
   a5 = str2double(line1(e1(4)+4:e1(5)+3));

   % Getting species with exponential coeifficent
   line2 = fgetl(f1);
    % Finding the location of exponent(E) for line 2
   e2 = strfind(line2,'E');
    % We are converting string to number
   a6 = str2double(line2(1:e2(1)+3));
   a7 = str2double(line2(e2(1)+4:e2(2)+3));
   a8 = str2double(line2(e2(2)+4:e2(3)+3));
   a9 = str2double(line2(e2(3)+4:e2(4)+3));
   a10 = str2double(line2(e2(4)+4:e2(5)+3));

   % Getting species with exponential coeifficent
   line3 = fgetl(f1);
   % Finding the location of exponent(E) for line 3
   e3 = strfind(line3,'E');
   % We are converting string to number
   a11 = str2double(line3(1:e3(1)+3));
   a12 = str2double(line3(e3(1)+4:e3(2)+3));
   a13 = str2double(line3(e3(2)+4:e3(3)+3));
   a14 = str2double(line3(e3(3)+4:e3(4)+3));
  
   % Defining Universal Gas Constant 'r'  
   r = 8.314;

   % Calling functions in main body: specific_heat,enthalpy,entropy  
   [cp] = specific_heat(a1,a2,a3,a4,a5,a8,a9,a10,a11,a12,T,lmt,r);
   [H] = enthalpy(a1,a2,a3,a4,a5,a6,a8,a9,a10,a11,a12,a13,T,lmt,r);
   [S] = entropy(a1,a2,a3,a4,a5,a7,a8,a9,a10,a11,a12,a14,T,lmt,r);

   % Creating new folder for species 
   mkdir(['C:\Users\mural\OneDrive\Desktop\THERMO.datO',species_name])
   % Entering current folder 
   cd(['C:\Users\mural\OneDrive\Desktop\THERMO.datO',species_name])
   % Plot 1 
   figure(1)
   plot(T,cp,'LineWidth',3,'Color','b')
   xlabel('Temperture')
   ylabel('Specific heat')
   title('Specific heat vs Temperture of',sprintf('%s',species_name))
   grid on 
   % Saveas saves figure to a specific format
   saveas(figure(1),'cp vs T.jpg')

   % Plot 1 
   figure(2)
   plot(T,H,'LineWidth',3,'Color','g')
   xlabel('Temperture')
   ylabel('Enthalpy')
   title('Enthalpy vs Temperture of',sprintf('%s',species_name))
   grid on 
   % Saveas saves figure to a specific format
   saveas(figure(2),'H vs T.jpg')

   % Plot 1 
   figure(3)
   plot(T,S,'LineWidth',3,'Color','m')
   xlabel('Temperture')
   ylabel('Entropy')
   title('Entropy vs Temperture of',sprintf('%s',species_name))
   grid on
   % Saveas saves figure to a specific format
   saveas(figure(3),'S vs T.jpg')
   
   %Returning back to initial directory
    cd ..

   [M] = mol_wt(species_name);
   K = sprintf('%s weight = %f',species_name,M);
   disp(K)
end

 fclose(f1);

CODE EXPLAINED:

• Initially we have to open the given THERMO.dat file using fopen command and then we will extract all the information provided in the file using fgetl command. and then we will get the global temperature by using strslplit command and then we have to skip some lines using the fget command.
• Now we have to use of for loop command to get all temperature and coefficients that are present in our file.
• Once we getting the temperature and coefficients, we use finstr command in order to input the accurate spot and specifying it so that we can get all the data.
• Now the data’s which are obtained from the file will be of string format which we need to convert into numbers by using str2num command. And by this we will get the temperature and coefficient of all the species.
• Now we make use of if command to create file for each species, in case if the folder exist it will simply save as plot or else it will create a folder to save the plot.
• Next, we have to calculate the specific heat, enthalpy, entropy function and gets plotted. The three figures are plotted using plot command and each species name is displayed using title command. And further it will be named using xlabel and ylabel command. This command is used for assuming the name of x-axis and y-axis
• Finally, we are changing the directory using cd command and then we will save the plots as our images using save command.
• Finally, we will again change the directory using cd command to calculate molecular weight of each species using the function program and closing the file using fclose command.

PLOT FOR H2:

PLOT FOR NH:

PLOT FOR C2H6:

Outputs:

This Screenshot denotes the plots for all the species:

RESULT:
The code for file parsing is done then it was plotted for H2 NH and C2H6 excetra. Finally we found the molecular weight for every elements and then the file was created.