Project 1 - Parsing NASA thermodynamic data

1)calculation of Cp , H, and S in high temp

Cp = (a1+a2*T+a3*T.^2+a4*T.^3+a5*T.^4)*R

H = (a1+0.5*a2*T+0.333*a3*T.^2+0.25*a4*T.^3+0.2*a5*T.^4+a6/T).*R.*T

S = (a1*log(T)+a2*T+0.5*a3*T.^2+0.333*a4*T.^3+0.25*a5*T.^4+a7)*R

2)calculation of Cp , H, and S in low temp

Cp = (a8+a9*T+a10*T.^2+a11*T.^3+a13*T.^4)*R

H = (a8+0.5*a9*T+0.333*a10*T.^2+0.25*a11*T.^3+0.2*a12*T.^4+a13).*R.*T

S = (a8*log(T)+a9*T+0.5*a10*T.^2+0.333*a11*T.^3+0.25*a13*T.^4+a14)*R

where

R = Characterstic gas constant

T = local temprature

a1 to a14 = cofficients

clear all 
close all
clc

f1 = fopen('THERMO.dat','r')  % open"THERMO" file for reading

for i=1:5                     %creating for loop for reading 1st five lines
    fgetl(f1)                 %reading line
end

for j = 1:53                  %initiation of for loop for all 53 species

line_1 = fgetl(f1);          %reading line 
a = strsplit(line_1,' ');    %split the string into cell
species_name = a{1}          %extract character 

len = length(a);             %define length

localmid  = str2num(a{len-1}) % extracting local mid temp and converted into numbers
localhigh  = str2num(a{len-2}) % extracting local high temp and converted into numbers
locallow  = str2num(a{len-3})  % extracting local low temp and converted into numbers

coff_line1 = fgetl(f1);                 % reading line 1 of cofficients
poss_E = strfind(coff_line1,'E')         % finding the position of 'E'

% finding out all cofficients in line 1
a1 = str2num(coff_line1(1:poss_E(1)+3));
a2 = str2num(coff_line1(poss_E(1)+4:poss_E(2)+3));
a3 = str2num(coff_line1(poss_E(2)+4:poss_E(3)+3));
a4 = str2num(coff_line1(poss_E(3)+4:poss_E(4)+3));
a5 = str2num(coff_line1(poss_E(4)+4:poss_E(5)+3));


coff_line2 = fgetl(f1);                   % reading line 2 of cofficients
poss_E2 = strfind(coff_line2,'E');        % finding the position of 'E'


% finding out all cofficients in line 2
a6 = str2num(coff_line2(1:poss_E2(1)+3))
a7 = str2num(coff_line2(poss_E2(1)+4:poss_E2(2)+3));
a8 = str2num(coff_line2(poss_E2(2)+4:poss_E2(3)+3));
a9 = str2num(coff_line2(poss_E2(3)+4:poss_E2(4)+3));
a10 = str2num(coff_line2(poss_E2(4)+4:poss_E2(5)+3));

% finding out all cofficients in line 3
coff_line3 = fgetl(f1);
poss_E3 = strfind(coff_line3,'E');

a11 = str2num(coff_line3(1:poss_E3(1)+3));
a12 = str2num(coff_line3(poss_E3(1)+4:poss_E3(2)+3));
a13 = str2num(coff_line3(poss_E3(2)+4:poss_E3(3)+3));
a14 = str2num(coff_line3(poss_E3(3)+4:poss_E3(4)+3));

T = linspace(locallow,localhigh,10);       % defining array of temp

R= 8.134;                                 % defining characterstic gas constant


for i = 1:length(T)                       % creating for loop for selecting temp from temp array

% initiation of if else loop    
if T>localmid                             % defining the condition 

% calculation of Cp , H, and S for if condition
Cp = (a1+a2*T+a3*T.^2+a4*T.^3+a5*T.^4)*R
H =   (a1+0.5*a2*T+0.333*a3*T.^2+0.25*a4*T.^3+0.2*a5*T.^4+a6/T).*R.*T
S = (a1*log(T)+a2*T+0.5*a3*T.^2+0.333*a4*T.^3+0.25*a5*T.^4+a7)*R

else
% calculation of Cp , H, and S for else condition
Cp = (a8+a9*T+a10*T.^2+a11*T.^3+a13*T.^4)*R
H =   (a8+0.5*a9*T+0.333*a10*T.^2+0.25*a11*T.^3+0.2*a12*T.^4+a13).*R.*T
S = (a8*log(T)+a9*T+0.5*a10*T.^2+0.333*a11*T.^3+0.25*a13*T.^4+a14)*R
end

cd('C:\Users\LENOVO\OneDrive\Desktop\matlab\5.1')          % changing the directory for new path
mkdir(species_name)    % creating directory
cd(species_name)       
figure(1)              % generating seperate figure
plot(T,Cp)             %plot between T and Cp
saveas(figure(1),'T vs cp.jpg')     %saving figure and specify its name
figure(2)
plot(T,H)
saveas(figure(2),'T vs H.jpg')
figure(3)
plot(T,S)
saveas(figure(1),'T vs s.jpg')
end


%CALCULATE MOLECULAR WEIGHT
species = species_name
atomic_names = ['H','C','O','N','A'];
atomic_weight = [1,12,16,14,40];
w = 0;
for i = 1:length(species)
    for j =1:length(atomic_weight)
        if species(i)==atomic_weight(j)
            w=w+atomic_weight(j);
            position = j;
        end
    end
    n = str2num(species(i));
    if n>=1
        w = w+atomic_weight(position)*(n-1)
    end

end


end

Command and function used:-

1.fopen - Use to make the given file readable to matlab.

2.fgetl - To read single line

3.strsplit - To split given string into cell

4.str2num - To convert string itno numbers

5.strfind - To find out the position of a charater of string

6.cd - To change the directory

7.mkdir - To create the directory

8.saveas - To save a given plot

Code Result

1 For O2

T vs cp

T vs H

T vs S

2 For N2

T vs cp

T vs H

T vs S

3 for co2

T vs cp

T vs H

T vs S