Project 1 - Parsing NASA thermodynamic data

Aim:- Write a code in matlab/Octave to parse the NASA thermodynamic data file and then calculate the thermodynamic properties of various gas species

Objective

1. To write a function that extracts the 14 co-efficients and calculates the enthalpy, entropy and specific heats for all the species in the data file. You will be reading this file NASA thermodynamic data(Tip:use fopen and fgetl).

2. To calculate the molecular weight of each species and display it in the command window.

3. To plot the Cp, Enthalpy and Entropy for the local temperature range (low temperature : high temperature) specific for each species.

4. To save the plots as images with appropriate names and dump them in separate folders for each species with suitable name. All these should be generated automatically.

5. The main program that you will submit will just take the "THERMO.dat" file as an input and generate Cp, H and S plots.

6. Screenshot of the window where all the folders are saved.

7. Plots for o2, N2 and Co2 speciesto be shown.

THE FORMULAE

Where

R = Universal Gas Constant

T = Temperature

Cp = Specific Heat (KJ)

S = Entropy (KJ/mol-K)

H = Enthalpy (KJ/mol)

a(i) = Coefficients where, i = 1 to 14

Definitions:

File Parsing

Parsing, syntax analysis, or syntactic analysis is the process of analyzing a string of symbols, either in natural language, computer languages or data structures, conforming to the rules of a formal grammar. The term parsing comes from Latin pars (orationis). meaning part (of speech), Within computational linguistics the term is used to refer to the formal analysis by a computer of a sentence or other string of words into its constituent, resulting in a parse tree showing their syntactic relation to reach other, which may also contain semantic and other information. Some parsing algorithms may generate a parse forest or list of parse trees for a syntactically ambiguous input.

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.

NASA Thermodynamic File:-

NASA Thermodynamic file which is THERMO.dat file in which there are temperature range and 53 species are given in these data and each species contains 14 coefficients and temperature ranges and we have to parse these 14 coefficients to find Specific heat, Entropy and Enthalpy using formulae.

Specific Heat:-

The specific heat is the amount of heat per unit mass required to raise the temperature by one degree Celsius.

Entropy:-

Entropy, the measure of a system’s thermal energy per unit temperature that is unavailable for doing useful work. Because work is obtained from ordered molecular motion, the amount of entropy is also a measure of the molecular disorder, or randomness, of a system.

Enthalpy:-

Enthalpy, a property of a thermodynamic system, is equal to the system’s internal energy plus the product of its pressure and volume. In a system contained so as to prevent mass transfer, for processes at constant pressure, the heat absorbed or released equals the change in Enthalpy.

PROGRAM:-

FUNCTIONS

Function to find specific Heat:-

% Specific Heat Calculation Function

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

STEPS:-

• Now we will find the Specific Heat by creating specific heat function and assigning its related formula coefficient from 14 coefficients, Gas constant, Temperature and mid temperature.
• Now we will create a condition using the “if” loop and make the temperature less than and equal to mid temperature to specify lower temperature coefficient in the formula.
• Then we will use the else condition to specify coefficient of Higher temperature coefficient in the formula.
• Then end the loop and function to calculate the “Specific Heat”.

Function to find Entropy:-

% Entropy Calculation Function

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

STEPS:-

• Now we will find the Entropy function and assigning its related formula coefficient from 14 coefficients, Gas constant, temperature and mid temperature..
• Now we will create a condition using the “if” loop and make the temperature less than and equal to mid temperature to specify lower temperature coefficient in the formula.
• Then we will use the else condition to specify coefficient of Higher temperature coefficient in the formula.
• Then end the loop and function to calculate the “Entropy”.

Function to find Enthalpy:-

% Enthalpy Calculation function

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

STEPS:-

• Now we will find the Enthalpy function and assigning its related formula coefficient from 14 coefficients, Gas constant, temperature and mid temperature..
• Now we will create a condition using the “if” loop and make the temperature less than and equal to mid temperature to specify lower temperature coefficient in the formula.
• Then we will use the else condition to specify coefficient of Higher temperature coefficient in the formula.
• Then end the loop and function to calculate the “Enthalpy”.

Function to find Molecular Weight of different Species:-

% Molecular Weight Calculation Function

function MW = Molecular_weight(species)
  
  % Defining Atomic Name of the species
  
  atomic_name = ['H', 'C', 'O', 'N', 'Ar'];
   % Hydrogen , Carbon, Oxygen, Nitrogen, Argon
   
   
   % Defining Atomic masses of main species
   atomic_weight = [1.008 12.011 15.999 14.007 39.948];
   
   MW = 0;                           % Molecular weight starting range
   
   % Adding Atomic Number to obtain particular value
   
   for  i=1:length(species)          % Loop runs to the length of the species
       for j=1:length(atomic_name)   % Loop runs to the length of the atomic name
         if strcmp(species(i), atomic_name(j)) % function to compare 2 strings
         MW = MW + atomic_weight(j);
         position = j;
       end
     end
     n = str2num(species);           % Finding more elements in the species and incrementing  atomic weight of the species
        
   if n>1
       MW = MW + atomic_weight(position)*(n-1);
     end
   end
   fprintf('Molecular Weight of %s : ',species);
   fprintf('%f',MW);
   disp(' ');
 end

STEPS:-

• Firstly we create an Molecular_weightfunction MW and assigning its species input to that.
• Then define the main element of all 53 species in an array atomic_name that are :- ‘H’,’C’,’O’,’N’,’Ar’.
• Then by taking the above main elements we will create thereatomic_weight array from any source like internet that are :- 008 12.011 15.999 14.007 39.948.
• Then we will assign molecular starting range from MW to zero and then create “for” loop condition which runs to the length of the species and an another nested “for” loop is created which runs to the length of the string atomic_name.
• Then we will create a condition using “If” condition and “strcmp” command to compare the species and atomic_name strings to calculate molecular masses if by comparison both string found same then we will assign its molecular weight.
• Now we will convert the string to numbers using “str2num” command and assign to then we run a condition of “if” loop to find whether the species contains more than one element and if there are more than 1 elements that is n>1 then we will increment the atomic weight by multiplication of position and n-1 to the atomic_weight array.
• Then we will print the molecular weight using fprintfcommand and display it using disp

MAIN CODE:-

clear all
close all
clc

% Input
R = 8.314; % Gas Constant (J/(mol-K))

% Reading data File
% Open and read THERMO.dat file

f1 =   fopen('THERMO.dat','r')
get = fgetl(f1);


% NOW reading Temperature from this file
temp = fgetl(f1);

% Splitting
s = strsplit(temp);

% Converting   strings cells into numbers
templow = str2num(s{2});
tempmid = str2num(s{3});
temphigh = str2num(s{4});

% Temperature Range
T = linspace(templow,temphigh,1000);

% Skipping Comment lines
for i= 1:3
    get = fgetl(f1);
    
endfor

% Reading the species 
for j = 1:53
  tline = fgetl(f1);
  
  
  A = strsplit(tline, ' ');   % Splitting cell into array
 
 species = (A{1});            % To read the name of the species
 
% Converting   strings cells into numbers
lowtemp = str2num(A{end-3});
midtemp = str2num(A{end-2});
hightemp = str2num(A{end-1});

tline1 = fgetl(f1);            % getting next line
a = strfind(tline1, 'E');      % Finding the string E

% Finding first 7 higher and second & lower coefficients

% Finding the Higher coefficients
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);
b = strfind(tline2, 'E');
a6 = tline2(1:b(1)+3);
a6 = str2num(a6);
a7 = tline2(b(1)+4:b(2)+3);
a7 = str2num(a7);


% Finding lower coefficients
a8 = tline2(b(2)+4:b(3)+3);
a8 = str2num(a8);
a9 = tline2(b(3)+4:b(4)+3);
a9 = str2num(a9);
a10 = tline2(b(4)+4:b(5)+3);
a10 = str2num(a10);

tline3 = fgetl(f1);
c = strfind(tline3, 'E');
a11 = tline(1:c(1)+3);
a11 = str2num(a11);
a12 = tline3(c(1)+4:c(2)+3);
a12 = str2num(a12);
a13 = tline3(c(2)+4:c(3)+3);
a13 = str2num(a13);
a14 = tline3(c(3)+4:c(4)+3);
a14 = str2num(a14);

% calculate specific heat
Cp = Specific_heat(a1,a2,a3,a4,a5,a8,a9,a10,a11,a12,T,R,tempmid);

% calculate Entropy
S = Entropy(a1,a2,a3,a4,a5,a7,a8,a9,a10,a11,a12,a14,T,R,tempmid);

% calculate Enthalpy
H = Enthalpy(a1,a2,a3,a4,a5,a6,a8,a9,a10,a11,a12,a13,T,R,tempmid);

% calculate Molecular Weight of the species
MW = Molecular_weight(species);

% writing molecular weight file
MW_file = fopen('Molecular Weight.txt','w');
fprintf(MW_file,'Molecular weight of %s is %d ',species,MW);
fclose(MW_file);                           % closing the file

% Plotting Cp, H & S with temperature
% saving in a folder
cd('C:/Users/karth/Week4 Test2/species')   % changing directory
mkdir(species);                            % creating directory
cd(species);

% Plot 1 | Cp vs T
figure(1)
plot(T,Cp,'linewidth',3,'color','r');
xlabel('Temperature (K)');
ylabel('Specific heat (KJ)');
title(sprintf('Specific heat vs Temperature range of %s', species));
grid on
saveas(figure(1),'Specific Heat.jpg');

% Plot 2 | S vs T
figure(2)
plot(T,S,'linewidth',3,'color','g');
xlabel('Temperature (K)');
ylabel('Entropy (KJ/mol-K)');
title(sprintf('Entropy vs Temperature range of %s', species));
grid on
saveas(figure(2),'Entropy.jpg');

% Plot 3 | H vs T
figure(3)
plot(T,H,'linewidth',3,'color','b');
xlabel('Temperature (K)');
ylabel('Enthalpy (KJ/mol)');
title(sprintf('Enthalpy vs Temperature range of %s', species));
grid on
saveas(figure(3),'Enthalpy.jpg');

cd('C:/Users/karth')                      % Changing directory to original matlab path

% Molecular Weight
MW = Molecular_weight(species)

end

STEPS:-

• Clear all, close all and clc is used to clear all previous commands and plots.
• ‘fopen’ is used to open the file named ‘dat’.
• ‘r’is used for read mode.
• ‘fgetl’is used to read the file line-by-line.
• ‘strplit’ command is used for splitting the string or character vectors at specified delimiter.
• ‘str2num’ command is used to convert character array or string to numeric array.
• Using ‘for & end’ loops to skip the next 3 comments
• ‘linspace’ is used to generate the temperature range.
• ‘for’ loop to read all 53 species one by one and plot them to different folder.
• ‘strfind’ to find one string within another
• All function defined previously like the “specific Heat, Entropy, Enthalpy & Molecular weight” are called one by one.
• Calculate and display molecular weight.
• ‘fclose’ is used to close the data file.

RESULTS & PLOTS:-

PLOTS

Plots for O2

Plots for N2

Plots for CO2

Screenshot of the directory where different species are saved:-

Molecular Weight of All species:- (Text & Screenshots)

f1 = 50
Molecular Weight of O : 15.999000
Molecular Weight of O : 15.999000
MW = 15.999
Molecular Weight of O2 : 15.999000
Molecular Weight of O2 : 15.999000
MW = 15.999
Molecular Weight of H : 1.008000
Molecular Weight of H : 1.008000
MW = 1.0080
Molecular Weight of H2 : 1.008000
Molecular Weight of H2 : 1.008000
MW = 1.0080
Molecular Weight of OH : 17.007000
Molecular Weight of OH : 17.007000
MW = 17.007
Molecular Weight of H2O : 17.007000
Molecular Weight of H2O : 17.007000
MW = 17.007
Molecular Weight of HO2 : 17.007000
Molecular Weight of HO2 : 17.007000
MW = 17.007
Molecular Weight of H2O2 : 17.007000
Molecular Weight of H2O2 : 17.007000
MW = 17.007
Molecular Weight of C : 12.011000
Molecular Weight of C : 12.011000
MW = 12.011
Molecular Weight of CH : 13.019000
Molecular Weight of CH : 13.019000
MW = 13.019
Molecular Weight of CH2 : 13.019000
Molecular Weight of CH2 : 13.019000
MW = 13.019
Molecular Weight of CH2(S) : 13.019000
Molecular Weight of CH2(S) : 13.019000
MW = 13.019
Molecular Weight of CH3 : 13.019000
Molecular Weight of CH3 : 13.019000
MW = 13.019
Molecular Weight of CH4 : 13.019000
Molecular Weight of CH4 : 13.019000
MW = 13.019
Molecular Weight of CO : 28.010000
Molecular Weight of CO : 28.010000
MW = 28.010
Molecular Weight of CO2 : 28.010000
Molecular Weight of CO2 : 28.010000
MW = 28.010
Molecular Weight of HCO : 29.018000
Molecular Weight of HCO : 29.018000
MW = 29.018
Molecular Weight of CH2O : 29.018000
Molecular Weight of CH2O : 29.018000
MW = 29.018
Molecular Weight of CH2OH : 30.026000
Molecular Weight of CH2OH : 30.026000
MW = 30.026
Molecular Weight of CH3O : 29.018000
Molecular Weight of CH3O : 29.018000
MW = 29.018
Molecular Weight of CH3OH : 30.026000
Molecular Weight of CH3OH : 30.026000
MW = 30.026
Molecular Weight of C2H : 13.019000
Molecular Weight of C2H : 13.019000
MW = 13.019
Molecular Weight of C2H2 : 13.019000
Molecular Weight of C2H2 : 13.019000
MW = 13.019
Molecular Weight of C2H3 : 13.019000
Molecular Weight of C2H3 : 13.019000
MW = 13.019
Molecular Weight of C2H4 : 13.019000
Molecular Weight of C2H4 : 13.019000
MW = 13.019
Molecular Weight of C2H5 : 13.019000
Molecular Weight of C2H5 : 13.019000
MW = 13.019
Molecular Weight of C2H6 : 13.019000
Molecular Weight of C2H6 : 13.019000
MW = 13.019
Molecular Weight of CH2CO : 41.029000
Molecular Weight of CH2CO : 41.029000
MW = 41.029
Molecular Weight of HCCO : 41.029000
Molecular Weight of HCCO : 41.029000
MW = 41.029
Molecular Weight of HCCOH : 42.037000
Molecular Weight of HCCOH : 42.037000
MW = 42.037
Molecular Weight of H2CN : 27.026000
Molecular Weight of H2CN : 27.026000
MW = 27.026
Molecular Weight of HCN : 27.026000
Molecular Weight of HCN : 27.026000
MW = 27.026
Molecular Weight of HNO : 31.014000
Molecular Weight of HNO : 31.014000
MW = 31.014
Molecular Weight of N : 14.007000
Molecular Weight of N : 14.007000
MW = 14.007
Molecular Weight of NNH : 29.022000
Molecular Weight of NNH : 29.022000
MW = 29.022
Molecular Weight of N2O : 30.006000
Molecular Weight of N2O : 30.006000
MW = 30.006
Molecular Weight of NH : 15.015000
Molecular Weight of NH : 15.015000
MW = 15.015
Molecular Weight of NH2 : 15.015000
Molecular Weight of NH2 : 15.015000
MW = 15.015
Molecular Weight of NH3 : 15.015000
Molecular Weight of NH3 : 15.015000
MW = 15.015
Molecular Weight of NO : 30.006000
Molecular Weight of NO : 30.006000
MW = 30.006
Molecular Weight of NO2 : 30.006000
Molecular Weight of NO2 : 30.006000
MW = 30.006
Molecular Weight of HCNO : 43.025000
Molecular Weight of HCNO : 43.025000
MW = 43.025
Molecular Weight of HOCN : 43.025000
Molecular Weight of HOCN : 43.025000
MW = 43.025
Molecular Weight of HNCO : 43.025000
Molecular Weight of HNCO : 43.025000
MW = 43.025
Molecular Weight of NCO : 42.017000
Molecular Weight of NCO : 42.017000
MW = 42.017
Molecular Weight of CN : 26.018000
Molecular Weight of CN : 26.018000
MW = 26.018
Molecular Weight of HCNN : 41.033000
Molecular Weight of HCNN : 41.033000
MW = 41.033
Molecular Weight of N2 : 14.007000
Molecular Weight of N2 : 14.007000
MW = 14.007
Molecular Weight of AR : 39.948000
Molecular Weight of AR : 39.948000
MW = 39.948
Molecular Weight of C3H8 : 13.019000
Molecular Weight of C3H8 : 13.019000
MW = 13.019
Molecular Weight of C3H7 : 13.019000
Molecular Weight of C3H7 : 13.019000
MW = 13.019
Molecular Weight of CH3CHO : 42.037000
Molecular Weight of CH3CHO : 42.037000
MW = 42.037
Molecular Weight of CH2CHO : 42.037000
Molecular Weight of CH2CHO : 42.037000
MW = 42.037
>>

Conclusion:-

Using Octave code, the necessary coefficients required to evaluate various thermodynamic parameters for different species are extracted from NASA thermodynamic data file. The spec ific heat, entropy & enthalpy for all the species are calculated and plotted against the local temperature range. The molecular weight is calculated for all the species.