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Sample Labview VI's

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Simple piece of Matlab code to process the data recorded by the Labview VI :

%********************
noc=473;
for i=1:noc
filename1=int2str(i);
filename2='.kat';
filename=[filename1,filename2];
arr=textread(filename,'%*f %f %*f','headerlines',8);
totaltemp=0;
for j=1:30000
totaltemp=arr(j)+totaltemp;
end
avg_case=totaltemp/30000;
stdsum=0;
for k=1:30000
stdsum=stdsum+(arr(k)-avg_case)^2;
end
std_deviation=sqrt((1/29999)*stdsum);
delta_t=std_deviation/sqrt(30000);
% hold on;
% plot(arr,'r.');
results(i,1)=avg_case;
results(i,2)=std_deviation;
results(i,3)=delta_t;
end
dlmwrite('results.kat',results(),'newline','pc')
clear;
% n = # of test cases
%****************
noc=473;
% u = free stream velocity in m/s , d = dia. of cylinder in metres
%(small cyl=0.00625, large cyl=0.00942)
% t_inf=free stream temp
%*****************
u=0.07;
d=0.00942;
t_inf=25.9;
%cdelt =c_delta value by calibration(sml cyl=0.00024, large cyl=0.00055)
% **the value u enter in the code SHUD BE positive even though its actually
% negative. check Pg.35 of Pottebaum thesis for values and eq.2.5 on Pg.28 for
% formula
%******************
cdelt=0.00055;
%R_d = radius in m (sml_cyl = 0.003125 , big_cyl = 0.00471)
R_d=0.00471;
%L=cylinder length (0.15875m)
L=0.15875;
%P= voltage * Current (calculate for each test run)!!!
P=59.20;
%*******************
load results.kat;
% tc_temp = average of thermocouple temp
tc_temp=results(:,1);
load parameters.txt;
%amp_inp= input amplitude , amp = actual amplitude of oscillation
amp_inp=parameters(:,1);
freq=parameters(:,2);
amp=amp_inp*2;
%amp_rads = amplitude in radians
amp_rads=amp*(pi()/180);
%f_star= non-dimensional frequency
f_star=freq*(d/u);
for i=1:noc
h(i)=1/(((2*pi()*R_d*L*(tc_temp(i)-t_inf))/P)-cdelt);
Nu(i)=h(i)*d/0.612;
end
%n_freq = no. of unique frequencies tested, n_amp= # of amplitudes tested
%***********************
n_freq=43;
n_amp=11;
Nu0=0;
for i=1:n_freq
Nu0=Nu0+Nu(i);
end
%Nu0=avg.Nu for amplitude=0 degrees case
Nu0=Nu0/n_freq;
%NHT=Normalized Heat Transfer
for i=1:noc
NHT(i)=Nu(i)/Nu0;
results_final(i,1)=tc_temp(i);
results_final(i,2)=amp(i);
results_final(i,3)=amp_rads(i);
results_final(i,4)=h(i);
results_final(i,5)=Nu(i);
results_final(i,6)=NHT(i);
results_final(i,7)=f_star(i);
c1(i,1)=1/f_star(i);
c1(i,2)=amp_rads(i);
c1(i,3)=NHT(i);
end
dlmwrite('results_final.kat',results_final(),'newline','pc')
dlmwrite('c1.kat',c1(),'newline','pc')
ii=0;
for j=1:n_amp
for i=1:n_freq
x(i)=f_star(i);
ii=ii+1;
y(i)=NHT(ii);
end
plot(x,y,'.-');
hold all;
% legend(j);
end
xlabel('f*');
ylabel('Nu / Nu0');
title('normalized heat transfer vs. f*');
grid on;
clear