Project 1 - Parsing NASA thermodynamic data

Aim :- To calculate Parsing NASA Thermodynamic data

Theory:- 

1.In the NASA format, coefficients of the NASA thermodynamic equations - heat capacity at constant pressure, standard enthalpy change and standard entropy change, for two different temperature regimes were available. The Group additivity format comprises of high charts of heat capacity at constant pressure, standard enthalpy change and standard entropy change as a function of temperature.

2.As no index of compounds was available in the database and as parsing data from highcharts using Python was tough, data from the NASA format was alone parsed. Since the temperature ranges varied across different libraries, the coefficients and their respective temperature ranges were parsed from the web servers and stored in a CSV format.

3.The data parsed was segregated based on the source library and the compound’s label within the library. The source code used for parsing data from the RMG web server can be accessed here.

What is Enthalpy?

Enthalpy is defined as a change in internal energy and volume at constant pressure. It deals with the heat contained in any system. Thereby, it changes when heat enters or leaves a system. For example, it increases when heat is added and decreases when heat is withdrawn from that system. There are some molecules that take part in this change are called “internal enthalpy” and the molecules that do not are referred to as “external enthalpy”. The enthalpy is represented through the following equation.

                                                   E= U+ PV

Where E is enthalpy, U is the internal energy of any system, P is pressure, and V is volume. 

What is Entropy?

Entropy is the measure of the disorder of the energy of a collection of particles. This idea is derived from Thermodynamics, which explains the heat transfer mechanism in a system. This term comes from Greek and means “a turning” point. It was first coined by Rudolf Clausius, a German physicist. He documented a precise form of the Second law of thermodynamics through entropy. 

It states that any spontaneous change in an isolated system for irreversible reaction always leads towards increasing entropy. For example, when we put a block of ice on a stove, these two make an integral part of a single isolated system. Thereby, the ice melts and entropy increases. Since all the spontaneous processes are irreversible, we can say that the entropy of the universe is increasing. Moreover, it can be concluded that more energy will be unavailable for work. Due to this, it is said that the universe is “running down”. 

The S.I unit of entropy is Joules per Kelvin. Also, it is expressed as ΔS, and the following is its equation. 

              ΔSsystem = Qrev / T

Where S denotes the change in entropy, Q denotes the reverse of heat and temperature is represented by T in the Kelvin scale. 

What is Specific?

specific heat, the quantity of heat required to raise the temperature of one gram of a substance by one Celsius degree. The units of specific heat are usually calories or joules per gram per Celsius degree. For example, the specific heat of water is 1 calorie (or 4.186 joules) per gram per Celsius degree.

1.Specific Heat Calculation:-

%Specific heat calculation

function Cp = Specificheat(a1,a2,a3,a4,a5,a8,a9,a10,a11,a12,Temp,R,global_medium_temp)
% Comparing with global temperature
% If less than global temperature - minimum coefficients are taken
if Temp <= global_medium_temp

    Cp = R*(a8 + (a9*Temp) + (a10*(Temp).^2) + (a11*(Temp).^3)+(a12*(Temp).^4));
else
    Cp = R*(a1 + (a2*Temp)+(a3*(Temp).^2) + (a4*(Temp).^3) + (a5*(Temp).^4));

    %Else maximun coefficients are taken
end

2.Entropy Calculation:-

% Entropy calculation function

function S = Entropy_calc(a1,a2,a3,a4,a5,a7,a8,a9,a10,a11,a12,a14,Temp,R,global_medium_temp)
% Comparing with global temperature
% If less than global temperature - minimun coefficients are taken

if Temp <= global_medium_temp

    S = R.*Temp.*(a8.*log(Temp) + (a9.*(Temp).^2)/2) + (a11*((Temp).^3)/3) + (a12*((Temp).^4)/4) + a14;
else

    % Else - maximum coefficient are taken

    S = R.*(a1.*log(Temp) + (a2.*Temp) + (a3*((Temp).^2)/2) + (a4*((Temp).^3)/3) + (a5*((Temp).^4)/4) + a7);

end

3.Enthalpy Calculation:-

% Enthalpy calculation function

function H = Enthalpy(a1,a2,a3,a5,a6,a8,a9,a10,a11,a12,a13,Temp,R,global_medium_temp)
% Comparing with global temperature
% If less than global temperature
% If less than global temperature - minimum coefficients are taken

if Temp <=global_medium_temp
    H = R*Temp.*(a8 + ((a9*Temp)/2) + ((a10*(Temp).^2)/3) +((a11*(Temp).^3)/4) + ((a12*(Temp).^4)/5) + ((a13./Temp)));
else

    % Else maximum coefficients are taken

   H = R*Temp.*(a1 + ((a2*Temp)/2) + ((a3*(Temp).^2)/3) + ((a4*(Temp).^3)/4) + ((a5*(Temp).^4)/5) + ((a6./Temp)));

end

4.Molecular Weight Calculation:-

% Molecular weight calculation function

function Molecularweight = Molecularweight(Species_SP)
% Standard - Atomic Name
atomic_name = ['H','C','O','N','A'];

% Hydrogen, Carbon, Oxygen, Nitrogen,Argon

fprintf('Molecular_weight of');
fprintf(Species_SP);
fprintf(' : ');

% Standard Atomic Number
Atomic_weight = [1.008 12.01 15.999 14.007 39.948];
%Starting Range of Molecule
Molecularweight = 0;

% Adding Atomic number to obtain particular value
for i = 1:length(atomic_name)
    if strcmpi(Species_SP(i),atomic_name(j))
        Molecularweight = Molecularweight + Atomic_weight(j);

        position = j;

    end

n = str2num(Species_SP(i));

if n>1

    Molecularweight = Molecularweight + Atomic_weight(position)*(n-1);
end

fprintf('molecularweight %s :',Species_SP');
fprintf('%d',Molecularweight);
disp('');

end

5.Main Code Calculation:-

% Main code program
clear all
close all
clc

% Make directory
mkdir'C:UsersAdminDesktopNASA File Parsing'

% Reading Data file - NASA  Thermodynamic
% Open a file & 'r' Open the file for reading
f1 = fopen('THERMO.dat','r')
gt = fgetl(f1)

%Obtaining Temperature - Reading Header Information
global_temp = fgetl(f1);

% Spliting
t = strsplit(global_temp);

% Converting string cells to number using str2num,

global_low_temp = str2num(t{2});
global_medium_temp = str2num(t{3});
global_high_temp = str2num(t{4});

% Temperature range & Gas Constant
% Temperature range assumed
Temp = linspace(gloabl_low_temp,global_high_temp,1000);

%Universal gas constant J/(mol-K)
R = 8.314;

% skipping three comment lines in the file
for i = 1:3
    gt = fgetl(f1);

end

for i = 1:53
    gt = fgetl(f1);
    A = strsplit(gt,'');
    Species_SP = (A{1})

    line_1 = fgetl(f1);
    a = strfind(line_1,'E');

    %Extracting higher and lower temperature coefficients

    %Extracting first 7 coefficient i.e High - temperature coefficients

    a1 = line_1(1:a(1) + 3);
    a1 = str2num(a1);     %1
    a2 = line_1(a(1) + 4:a(2)+3);
    a2 = str2num(a2);     %2
    a3 = line_1(a(2) + 4:a(3)+3);
    a3 = str2num(a3);    %3
    a4 = line_1(a(3) + 4:a(4)+3);
    a4 = str2num(a4);    %4
    a5 = line_1(a(4) + 4:a(5)+3);
    a5 = str2num(a5);   %5

    line_2 = fgetl(f1);
    b=strfind(line_1,'E');
    a6=line_2(1:b(1)+3);
    a6=str2num(a6);    %6
    a7=line_2(a(1)+4:b(2)+3);
    a7 = str2num(a7);   %7

   %Extracting  second 7 coefficient - low temperature coefficients

   a8=line_2(b(2)+4:b(3)+3);
   a8 = str2num(a8);   %8

   a9=line_2(b(3)+4:b(4)+3);
   a9 = str2num(a9);  %9
   a10=line_2(b(4)+4:b(5)+3);
   a10=str2num(a10);  %10

   line_3 = fgetl(f1);
   c= strfind(line_1,'E')

   a11 = line_3(1:c(1)+3);
   a11 = str2num(a11);   %11

    a12 = line_3(c(1)+4:c(2)+3);
    a12 =str2num(a12);   %12

    a13 = line_3(c(2)+4:c(3)+3);
    a13 = str2num(a13);  %13

    a14 = line_3(c(3)+4:c(4)+3);
    a14 = str2num(a14);    %14

    % Specific heat calculation

    Cp = Specificheat (a1,a2,a3,a4,a5,a8,a9,a10,a11,a12,Temp,R,global_medium_temp);

    %Enthalpy calculation
    H = Enthalpy(a1,a2,a3,a4,a5,a6,a8,a9,a10,a11,a12,a13,Temp,R,global_medium_temp);

   %Entropy calculation
    S = Entropy_calc(a1,a2,a3,a4,a5,a6,a8,a9,a10,a11,a12,a14,Temp,R,global_medium_temp);

    % Calculating molecular weight of species

   Molecularweight(i) = molecular_wt(Species_SP);

   %Read & Write Molecular list
   Molecular_list = fopen('Molecular weight.txt','a+');
   fprintf(Molecular_list,'Molecular weight of %s is %d n',Species_SP,Molecularweight);
   fclose(Molecular_list);

   %plotting(CP,H,S,Temp,Species_SP)

   %Saving as a folder

   cur_dir=pwd;
   mkdir(Species_SP);
   cd(Species_SP);

   %Plot 1, Specific heat(CP) vs Temperature Range (Temp)

   figure(1)
   plot(Temp,Cp,'linewidth',2,'color','r')
   xlabel('Temperature [K]');
   ylabel('Specific Heat[kj]');
   title(sprintf('Varying Specific Heat with Temperature Range of %s',Species_SP));
   grid on
   saveas(figure(1),'Specific Heat.jpg');

   %Plot2, Enthalpy (H) vs Temperature Range (Temp)
   figure(2)
   plot(Temp,H,'linewidth',2,'color','g')
   xlabel('Temperature [K]');
   ylabel('Specific Heat[kj/(mol)]');
   title(sprintf('Varying Enthalpy with Temperature Range of %s',Species_SP));
   grid on
   saveas(figure(2),'Enthalpy.jpg');

   % Plot 3, Entropy(S) vs Temperature Range (Temp)
   figure(3)
   plot(Temp,S,'linewidth',2,'color','b')
   xlabel('Temperature [K]');
   ylabel('Entropy in [kj/(mol-K)]');
   title(sprintf('Varying Entropy with Temperature Range of %s',Species_SP));
   grid on
   saveas(figure(2),'Entropy.jpg');

   cd(cur_dir);

   % Molecular weight
   M = Molecular_weight(Species_SP)
   f2 = fopen('molecular mass','w');
   fprintf('%s n %s n %f n','species','Molecular mass',M)
   fclose(f2)

end

6.Program File Save Folder:-

7.Results:-

A.Plot for O2

1.Variation with specific heat with temperture of O2 :-

a.Variation of specific heat with the temperture of O2

b.Variation of Entropy with the temperture of O2

c.Variation of Enthalpy with the temperture of O2

B.Plot for N2

1.Variation with specific heat with temperture of N2 :-

b.Variation of Entropy with the temperture of N2:-

c.Variation of Enthalpy with the temperture of N2:-

C.Plot for CO2

1.Variation with specific heat with temperture of CO2 :- 

b.Variation of Entropy with the temperture of CO2:-

c.Variation of Enthalpy with the temperture of CO2:-