I have 2 error .Error using interp1>re​shapeAndSo​rtXandV (line 445) X and V must be of the same length. Error in interp1 (line 128) [X,V,orig_size_v] = reshapeAndSortXan

>> %% Turbine Design Parameters

R = 1; % Turbine Radius

N = 1; % Number of Blades

c = 1; % Chord Length

L = 1; % blade Height

%% Operating Parameters

Vo = 1:1:7; % Free Stream Velocity (m/s)

n=36; % Number of Streamtubes ( 180 / 5 = 36 ) ???

w =1:1:7; % Angular Velocity (rad/s)

Xt = w.*R./Vo; %Tip speed ratio

Ao = 3; % initial angle of attack (rad)

%% CONSTANTS FOR STANDARD AIR CONDITIONS AND SEA LEVEL

kv = 1.4607*(exp(-5)); % Kinematic viscosity at 15oC [m^2/s] ???

rho = 1.225; % air density (Standard density at sea level)[kg/m^3] at sea level ????

%% Process

S = 2*L*R; %Swept area [m^2]

theta = -90;

theta2 = -89;

st = 1;

thetau = zeros(1, n); % initialize the arrays

thetad = zeros(1, n);

for st = 1:1:36

if theta < 0

theta = theta + 360;

end

if theta2 < 0

theta2 = theta2 + 360;

end

if theta - 360 < 0 % ?????

theta = theta - 360 + (179 / 36) ;

else

theta = theta + (179 / 36);

end

if theta2 - 360 < 0

theta2 = theta2 - 360 - (179 / 36);

else

theta2 = theta2 - (179 / 36);

end

thetau(st) = theta * pi / 180;

thetad(st) = (theta2) * pi / 180;

end

Vu = Vo;

%%---------------UPSTREAM CALCULATION---------------------

i = 0; %initialize the counter value

while (i~=n)

i = i+1;

% Wu=local resultant air velocity

Wu = sqrt( Vu.^(2).*( (Xt - sin ( thetau(i))).^(2) + (cos ( thetau(i))).^(2)));

Reb = Wu*c/kv; %Local Blade Reynolds number

%% Airfoil

% Type of airfoil

typeNACA = '2412';

% Extracrt values from type of airfoil string

Minit = str2double(typeNACA(1));

Pinit = str2double(typeNACA(2));

Tinit = str2double(typeNACA(3:4));

% Actual percentage values of airfoil properties

M = Minit/100;

P = Pinit/100;

T = Tinit/100;

%%

%if NACA == 15

%[A1, Cl1, Cd1] = NACAfinder15(Reb);

%else

%[A1, Cl1, Cd1] = NACAfinder21(Reb);

%end

A1=0:5:180;

cd1=1:1:35;

cl1=2:1:37;

costh = cos(thetau(i));

cosao = cos(Ao);

sinth = sin(thetau(i));

sinao = sin(Ao);

A =asin(costh.*cosao-(Xt-sinth).*sinao / sqrt((Xt-sinth).^2+(costh.^2)));

Cd = interp1(A1,cd1,A,'linear');

Cl = interp1(A1,cd1,A,'linear');

switch true

case 0<A && A<60

Cd = 0.5;

Cl = 0.5;

case 60<=A && A<140

Cd = (200 - 2 * Ao) / 80;

Cl = (200 - 2 * Ao) / 80;

case 140<=A && A<160

Cd = (A - 173.33) / 26.66;

Cl = (A - 173.33) / 26.66;

case 160<=A && A<180

Cd = (A - 180) / 80;

Cl = (A - 180) / 80;

end

au = 1.01; % velocity induction factor upstream

newau = 1; % initialize, au must be different from newau ??????

while (au-newau)>(10^(-3))

Vu = Vo*(au); %Vu =velocity upstream of wind turb

X = R*w/Vu; %Local Tip speed ratio

if ((A) < 0)

A = -1 * A;

Cl = -1 * Cl;

end

% Wu=local resultant air velocity

Wu = sqrt( Vu^(2)*( (X - sin ( thetau(i)))^(2) + (cos ( thetau(i)))^(2)));

% interp1 is 1-D data interpolation for example x goes 1 to 5 , y has 6

% point and also you can define 18 points on that figure, those 6 points

% are main points for your graph but also the other 18 points are wanted to

% show on that figure.

%% Continue

% Cn = normal coefficient, % Ct = tangential coefficient

Cnu = Cl*cosd (A) + Cd*sind (A); %note that A is in degrees

Ctu = Cl*sind (A) - Cd*cosd (A);

% fup = function to find interference factor (au)

g=@(thetau) (abs(sec (thetau)).*(Cnu.*cos(thetau) - thetau) - Ctu.*sin(thetau)).*(Wu./Vu).^2;

for g = 0:10

fup(g) = ((Abs(1 / ((Cos((-pi / 2) + (g * pi /10)))))) * (cnu * Cos((-pi / 2) + (g * pi / 10)) - ctu * Sin((-pi / 2)+ (g * pi / 10))));

actfup = (N * c* y / (8 * pi * R ))* ((pi / 30) * ((fup(0) + fup(10)) + (4 * (fup(1) + fup(3) + fup(5) + fup(7) + fup(9))) + 2 * (fup(2) + fup(4) + fup(6) + fup(8))));

end

newau = pi/(actfup+pi); % new interference factor value for the next iteration process

Fnu = (c*L/S)*Cnu*(Wu/Vo)^2; % normal force coefficient

Ftu = (c*L/S)*Ctu*(Wu/Vo)^2; % tangential force coefficient

Tup(i) = 0.5*rho*c*R*L*Ctu*(Wu^2);

av_tup_i = (1 / 3) * ((Tup(1) + Tup(36)) + 4 * (Tup(3) + Tup(5) + Tup(7) + Tup(9) + Tup(11) + Tup(13) + Tup(15) + Tup(17) + Tup(19) + Tup(21) + Tup(23) + Tup(25) + Tup(27) + Tup(29) + Tup(31) + Tup(33) + Tup(35)) + 2 * (Tup(2) + Tup(4) + Tup(6) + Tup(8) + Tup(10) + Tup(12) + Tup(14) + Tup(16) + Tup(18) + Tup(20) + Tup(22) + Tup(24) + Tup(26) + Tup(28) + Tup(30) + Tup(32) + Tup(34)));

av_Tup = N*(av_tup_i)/(2*pi); % up stream average torque

av_Cqu = av_Tup/(0.5*rho*S*R*Vo^2);

Cpu = av_Cqu*Xt; % Upstream power coefficient

Auvector (i) = A; % Store angle of attack value

auvector (i) = newau; % Store au value in a vector

end

%%---------------DOWNSTREAM CALCULATION---------------------

j = n+1;

flag =0;

i = 0; %initialize the counter

while (j~=1)

j = j-1;

i = i+1; % interference factor downstream.

ad = 1.01; % velocity induction factor upstream

newad = auvector(j); % initialize, au must be different from newau

while (ad-newad)> 0.001 %Iterative process to find ad

ad = newad;

Ve = Vo*((2*auvector(j))-1); %Ve = air velocity inside cylinder

Vd = Ve*ad;

if vd > 0

X = r * w / vd;

else

X = ve * 1.01;

end

Wd = sqrt ( Vd^2*( (X -sin (thetad(i)))^2 + (cos (thetad(i)))^2));

Reb = Wd*c/kv;

if NACA == 15

[A1, Cl1, Cd1] = NACAfinder15(Reb);

else

[A1, Cl1, Cd1] = NACAfinder21(Reb);

end

costh = cos(thetad(i));

cosao = cos(Ao);

sinth = sin(thetad(i));

sinao = sin(Ao);

A2 = asin((costh*cosao -(X-sinth)*sinao)/sqrt((X-sinth)^2+(costh^2)));

neg = 0;

if ((A2) < 0)

neg = 1

end

A2 = abs(A2*180/pi);

Cl = interp1 (A1, Cl1, A, 'linear');

Cd = interp1 (A1, Cd1, A, 'linear');

switch A2

case 0<A && A<60

cd = 0.5;

Cl = 0.5;

case 60<A && A<140

cd = (200 - 2 * Ao) / 80;

Cl = (200 - 2 * Ao) / 80;

case 140<A && A<160

cd = (Ao - 173.33) / 26.66;

Cl = (Ao - 173.33) / 26.66;

case 160<A && A<180

cd = (Ao - 180) / 80;

Cl = (Ao - 180) / 80;

end

if (neg==1)

A2 = -1*A2;

Cl =-1*Cl;

Cd =1*Cd;

end

Cnd = Cl*cosd (A2) + Cd*sind (A2);

Ctd = Cl*sind (A2) - Cd*cosd (A2);

g=@(thetad) (abs(sec (thetad)).*(Cnd.*cos(thetad) - Ctd.*sin(thetad)).*(Wd./Vd).^2);

for g1 = 0 : 10

y = integral (@g, 91*pi/180, 269*pi/180);

fdw(g1) = ((abs(1 / (cos((-pi / 2) + (g1 * pi / 10))) ^ (-1))) * (Cnu * cos((-pi / 2) + (g1 * pi / 10)) - Ctu * sin((-pi / 2) + (g1 * pi / 10))));

actfdw = (N * c * y / (8 * pi * r)) * ((pi / 30) * ((fdw(0) + fdw(10)) + (4 * (fdw(1) + fdw(3) + fdw(5) + fdw(7)+ fdw(9))) + 2 * (fdw(2) + fdw(4) + fdw(6) + fdw(8))));

end

if (flag ==0)

newad = pi/(fdw+pi);

end

if (newad<0.01)

warning('newad< 0.01 at theta = %d and A = %d', (thetad(i)*180/pi), A);

if (i>1)

newad = advector(i-1);

else

newad = auvector (i);

end

flag = 1;

end

end

Advector (i) = A;

advector (i) = newad;

Fnd (i) = (c*L/S)*Cnd*(Wd/Vo)^2; % normal force coefficient

Ftd (i) = (c*L/S)*Ctd*(Wd/Vo)^2; % tangential force coefficient

Tdw (i) = 0.5*rho*c*R*L*Ctd*Wd^2;

end

end

% Average upstream torque

ts4 = f_trapezoidal_integration_s (thetad, Tdw);

av_Tdw = N*(ts4)/(2*pi); % upstream average torque age torque

% Average torque coefficient

av_Cqd = av_Tdw/(0.5*rho*S*R*Vo^2);

Cpd = av_Cqd*Xt; % downstream power coefficient

Cpt = Cpd+Cpu; % Total power coefficient

av_T = av_Tup + av_Tdw; % Total average torque [Nm]

Error using interp1>reshapeAndSortXandV (line 445)

X and V must be of the same length.

Error in interp1 (line 128)

[X,V,orig_size_v] = reshapeAndSortXandV(X,V);

[ayse kaplan]

I can not this error solution .can you solve help these error?

Answer 1

[Askic V]

Please have a look at the documentation for the information how to use interp1 function correctly:

https://www.mathworks.com/help/matlab/ref/interp1.html?searchHighlight=interp1&s_tid=srchtitle_interp1_1

You're geeting this error because of this:

A1=0:5:180;
size(A1) % check dimensions
cd1=1:1:35;
size(cd1) % check dimensions

As you can see, A1 has 37 points and cd1 only 35. That is why interp1 is complaining and telling you that A1 (X) and cd1 (V) must be of the same length.