Engineering thermodynamics/Steam tables/Superheated (small)/Generating code

From Wikiversity
Jump to navigation Jump to search


The Excel spreadsheet Parameters.xlsx, as well as two Matlab files (XSteam.m, TableGraphmaker.m) must be placed in a folder. Run TableGraphmaker.m to generate the table and figures. The first row of Parameters.xlsx contains the pressures (bars). Each column (after the first row) contains the temperatures (Celsius) for that column.

Click to view or hide the codes and tables

Parameters.xlsx[edit | edit source]

This spreadsheet is used to generate the table (not the actual pressures and temperatures used)
25 50 100 150 200 250 300 350 400 450 500
200 200 200 200 200 200 200 200 200 200 200
250 250 250 250 250 250 250 250 250 250 250
300 300 300 300 300 300 300 300 300 300 300
350 350 350 350 350 350 350 350 350 350 350
400 400 400 375 375 375 375 375 375 400 400
450 450 450 400 400 400 400 400 400 450 450
500 500 500 425 425 425 425 425 425 500 500
450 450 450 450 450 450
500 500 450 500 500 500
500 500


TableGraphMaker.m[edit | edit source]

creates the graphs and the wikitext for the tables.
clear all;close all;clc;
% On 4/16/2015 I changed tempfix from .09 to .001
tempfix = .001;%tempfix = .09; %ideal is zero.  This is added to T so that T critical calculates parameters
presfix=.000001; %added so that pressure is above critical

Tmin =200; Tmax=500; %Is this needed?
Tphase = linspace(Tmin,373.9,500);

linewidth=1.2;  markersize = 5;
% This makes a T_versus_s plot

% There are two user selected paramters that often seemed necessary.  Make
% them as small as possible.  The problem is that calling XSteam at a
% saturation value sometimes yields odd results.

%These cell arrays are used to call the various state variables
Call ={'v_pT', 'u_pT','h_pT','s_pT' };
%Label ={'v (m^3/kg)', 'u (kJ/kg)','h (kJ/kg)','s(kJ/kg)','T (°C)', 'p (bars)' };
Label ={'v', 'u','h','s','°C','bars' };
plotcall ={'v_pT', 'u_pT','h_pT','s_pT' }; 
phasecall ={'vL_T','uL_T','hL_T','sL_T'}; %For liquid-gas phase
phasecallG ={'vV_T','uV_T','hV_T','sV_T'}; %For liquid-gas phase

sigfigs = '%10.2E'; %Use  '%10.3E' for  big table and '%10.3E' for compact table.
%Here are some paramters we don't seem to need:  %Rwater=461.526/100000;  %Tcritical = 374; %Pcritical = 220.6395 %bar
%% Read parameters and replace NAN by -1
parameters= xlsread('parameters.xlsx'); %Omit saturation temperatures or they will be repeated
[NTfirst,Np]=size(parameters);
for nT=1:NTfirst %Fills non numbers with -1
    for np=1:Np
        if isnan(  parameters(nT,np) )==1 % i.e., we are above saturation pressure  '
            parameters(nT,np)=-1;
        end
    end
end
% Define p as pressure array
p=parameters(1,:); %Defines p;

%%  fill the first row of parameters with saturation temperatures, when they exist
% Also, define T: T(1) is large to ensure evaluation by XSteam, so we must
% subtract tempfix everytime we print the saturation temperature.
for np = 1:Np
    if isnan(   XSteam('Tsat_p',p(np))  )==0 %  if Tsat exists
        parameters(1,np)=XSteam('Tsat_p',p(np))+tempfix;%added tempfix to ensure return%
    else parameters(1,np)=-1;
    end
end

%% Make wikitable header
fout=fopen('wikitable.txt', 'w+');% creates wikitext
for np=1:Np
    T=parameters(:,np); %need to define the temperatures after
    stringp=num2str(p(np),'%10.0f'); % is the pressure Changed to float4/17/2015
    if T(1)>0
        stringT = num2str(T(1)-tempfix,'%10.0f'); % is the saturation temperature
        %On 4/16/2015 the precision was changed from 10.1f to the above
        %10.0f for saturation temperatures.
        commentInHeader{np} = [' bars  &nbsp; &nbsp; (T<sub>sat</sub> = ',stringT,' &deg;C)===='];
        belowCrit=true;
    else %above critical pressure
        belowCrit=false;
        commentInHeader{np} = ' bars &nbsp; &nbsp; (above critical)====';
    end
    fprintf(fout,'%s\n',['====P = ',stringp,commentInHeader{np}]);
    %fprintf(fout,'%s\n','{| class="wikitable" style="text-align:center;  width:600px;" ');
    fprintf(fout,'%s\n','{| class="wikitable" style="text-align:center; " ');
    fprintf(fout,'%s\n','|-');
    % fprintf(fout,'%s\n',['|',' ','||', ' ', '||', ' ', '||' ,' ', '||', stringp ]);fprintf(fout,'%s\n','|-');
    string = ['|', Label{5}, '||' , Label{1}, '||', Label{2}, '||', Label{3}, '||', Label{4} ];
    fprintf(fout,'%s\n',string);
    %% print entries
    for nT = 1:NTfirst
        printline=0;
        
        if nT==1 && T(nT)>0, printline=1; end;
        if nT>1 && T(nT)>T(1), printline=1; end;
        
        if printline==1
            stringT = num2str(T(nT),'%10.0f');
            if nT==1 stringT='Sat'; end;
            stringv = num2str(XSteam('v_pT',p(np), T(nT)),sigfigs);
            stringu = num2str(XSteam('u_pT', p(np), T(nT)),sigfigs);
            stringh = num2str(XSteam('h_pT', p(np), T(nT)),sigfigs);
            strings = num2str(XSteam('s_pT', p(np), T(nT)),sigfigs);
            fprintf(fout,'%s\n','|-');
            fprintf(fout,'%s\n',['|',stringT,'||', stringv, '||', stringu, '||' ,stringh, '||', strings ]);
            if nT==1
                T(nT)=T(nT)+tempfix; %restore, just in case
            end
        end
    end
    fprintf(fout,'%s\n','|}');
end
fclose(fout);
%%

for count=1:4 %try this breakup
    what2plot = plotcall{count};
    
    for np=1:Np %create Tplot and Xplot
        clear Tplot Xplot; %and build up the temperatures for a contour
        T=parameters(:,np);
        %plotthis=0;
        firstplot=1; %default values
        for nT = 1:NTfirst   %begin search of a point worth plotting
            if T(nT)>=T(1),
                % plothis=1;
                if firstplot==1 %first element in both arrays
                    
                    Xplot = XSteam(plotcall{count}, p(np), T(nT) );
                    Tplot =T(nT);
                    firstplot = 0; %on next iteration do the following else
                else
                    Xnext = XSteam(plotcall{count}, p(np), T(nT) );
                    Tnext =T(nT);
                    Xplot = [Xplot,Xnext];
                    Tplot = [Tplot,Tnext];
                end %if firstplot==1 xxx else xxx
            end %if plotthis
        end; %for nT
        %%Make one  countour of the subplot
        subplot(2,2,count);
        if np == 1
          plot(Xplot,Tplot,':','LineWidth',linewidth) 
        else
        plot(Xplot,Tplot,'-o','LineWidth',linewidth,'MarkerSize',markersize)   
        end
        hold on; %Go to the next countour
        
    end %for np % we are done with all the countours
    
    % Add Liquid and Gas phase transition
    for n = 1:size(Tphase,2)
        Xphase(n) = XSteam(phasecall{count},Tphase(n) );
    end
    for n = 1:size(Tphase,2)
        XphaseG(n) = XSteam(phasecallG{count},Tphase(n));
    end
    plot(Xphase,Tphase,'r', 'Linewidth',linewidth)
    plot(XphaseG,Tphase,'m','Linewidth',linewidth)
     
    xlabel(Label{count});
    ylabel(['T=Temperature ( ^{\circ}C)']);
    if count==1 xlim([0 .1]); else xlim auto; end;
    ylim([Tmin Tmax+1]);
    hold off;
    
end %for count


LongTableMaker.m=[edit | edit source]

creates the table in a single column
%LongTableMaker creates the table in a single column
clear all;close all;clc;
%don't need:  %Rwater=461.526/100000;  %Tcritical = 374; %Pcritical = 220.6395 %bar
tempfix = .001; %ideal is zero.  This is added to T so that T critical calculates parameters
presfix=.000001; %added so that pressure is above critical
sigfigs = '%10.2E'; %Use  '%10.3E' for  big table and '%10.3E' for compact table.
%% Read parameters and replace NAN by -1
parameters= xlsread('parameters.xlsx'); %saturation temperatures absent
[NTfirst,Np]=size(parameters);
for nT=1:NTfirst %Fills non numbers with -1
    for np=1:Np
        if isnan(  parameters(nT,np) )==1 % i.e., we are above saturation pressure  '
            parameters(nT,np)=-1;
        end
    end
end
% Define p as pressure array
p=parameters(1,:); %Defines p;

%%  fill the first row of parameters with saturation temperatures, when they exist
% Also, define T: T(1) is made slightly large to ensure evaluation by XSteam, so we must
% subtract tempfix everytime we print the saturation temperature.
count=1;
for np = 1:Np
    if isnan(   XSteam('Tsat_p',p(np))  )==0 %  if Tsat exists
        temp=XSteam('Tsat_p',p(np))+tempfix ;%added tempfix to ensure return%
        parameters(1,np)= temp; % changed from str2num(sprintf('%.1f',temp))
        %with above change the saturation temperature is a float
    else parameters(1,np)=-1;
    end
    for nT = 1:NTfirst
        T = parameters(:,np);
        
        printline=0;
        if nT==1 && T(nT)>0, printline=1; end;
        if nT>1 && T(nT)>T(1), printline=1; end;
        if printline==1
            if T(nT)>0  %we have a value of T that we want to keep
                stringT = num2str(T(1)-tempfix,'%10.0f');
                longtable{count,1} =  num2str(p(np),'%10.0f');
                longtable{count,2} =  num2str(T(nT),'%10.0f');
                longtable{count,3}=  num2str(XSteam('v_pT',p(np), T(nT)),sigfigs) ;
                longtable{count,4}= num2str(XSteam('u_pT', p(np), T(nT)),sigfigs);
                longtable{count,5}=  num2str(XSteam('h_pT', p(np), T(nT)),sigfigs);
                longtable{count,6}= num2str(XSteam('s_pT', p(np), T(nT)),sigfigs);
                
                count = count + 1;
            end
        end
    end
end
endcount=count-1;