Processing ACII Fluent data on a corregated wall

i have a ACII fluent data from a corregation wall analysis. For unknow reasen on the wall and in the close area of the wall, some wavey structure are acour(in the image), my wall have constant heat flux which mean it shoude be a smoth transition. i think it the interpulation but i dont know how to solve it? i add some of my data(one part of incline wall) with x y and T acoredently

function [data] = openFile()

%Open a file dialog to choose a file
[file, path] = uigetfile('*.*', 'Select an ASCII file to open');

% Check if a file was selected
if isequal(file, 0) || isequal(path, 0)
    disp('No file selected.');
else
    % Concatenate the path and file name
    fullFilePath = fullfile(path, file);
    
    % Specify the file type as 'text' explicitly
    try
        data = readtable(fullFilePath, 'FileType', 'text');
        disp(['Successfully loaded file: ' fullFilePath]);
        % Now you can work with the 'data' table
    catch
        disp('Error reading the file.');
    end
end


%%
data = openFile(); %get flow data
dataWall = openFile(); %get wall data


%Coregation flow data
x = data.x_coordinate; 
y = data.y_coordinate;
u = data.x_velocity;
v = data.y_velocity;
T = data.temperature;
V = data.velocity_magnitude;
P = data.pressure;
Tw = dataWall.temperature;
Xw = dataWall.x_coordinate; 
Yw = dataWall.y_coordinate; 
% Set a high DPI value (e.g., 300 or 600) for high resolution (optional)
dpi = 600;

%% Calculating Nu as function of x 
L =  length(Xw); %y vector length%
xnew = sort(Xw);% defiend x location along the tunnel%
TV = T.*V;%T moltiply by V coralation%
Tm = [];um = [];
for i = 1:L
        um(i) = trapz(y(x==xnew(i)),V(x==xnew(i)))./h;
        Tm(i) = trapz(y(x==xnew(i)),TV(x==xnew(i)))./(um(i)*h);
end

Tw_new = [];
Tw_new(:,1) = Xw;
Tw_new(:,2) = Tw;
Tw_new1 = sortrows(Tw_new,1);
Twall = Tw_new1(:,2);
% The heat transfer coeffition%
hf = q./(Twall'-Tm);
Numean = mean((hf*Dh)/k);
Nu = (hf*Dh)/k;



%For flat plat
L =  length(xTwF); %y vector length%
x_newF = sort(xTwF);% defiend x location along the tunnel%
TVf = Tf.*Vf;%T moltiply by V coralation%
um = [];TmF=[];
for i = 1:L
        um(i) = trapz(yf(xf==x_newF(i)),Vf(xf==x_newF(i)))./h;
        TmF(i) = trapz(yf(xf==x_newF(i)),TVf(xf==x_newF(i)))./(um(i)*h);
end

Tw_newF = [];
Tw_newF(:,1) = xTwF;
Tw_newF(:,2) = TwF;
Tw_new1F = sortrows(Tw_newF,1);
TwallF = Tw_new1F(:,2);
% The heat transfer coeffition%
hfF = q./(TwallF'-TmF);
Nuf = (hfF*Dh)/k;

%% new interpulation
%Present the adge of the coregation
X_set(:,2) = min(x)+0.005:0.01:max(x)+0.005;%uper adge
X_set(:,1) = min(x):0.01:max(x);%lower adge
Y_max = 0.0035;
Y_min = 0;
desired_columns = 2000;
Mx_up=[]; My_up=[];Mx_down=[]; My_down=[];
vn_up=[];un_up=[];Tn_up=[];Pn_up=[];
vn_down=[];un_down=[];Tn_down=[];Pn_down=[];
for i =1:length(X_set)
    %incline ogf the wall
    x_new = linspace(X_set(i,1), X_set(i,2), desired_columns);
    y_new = linspace(0, Y_max, desired_columns);
    [Mx_up(:,:,i) My_up(:,:,i)] = meshgrid(x_new,y_new);
    %decline of the wall
    if i <13
    x_new = linspace(X_set(i,2),X_set(i+1,1), desired_columns);
    y_new = linspace(0, Y_max, desired_columns);
    [Mx_down(:,:,i) My_down(:,:,i)] = meshgrid(x_new,y_new); 
    end
end
 

    vn_up=[]; un_up=[]; Pn_up=[]; Tn_up=[];
    vn_down=[]; un_down=[];  Tn_down=[]; Pn_down=[];

for i = 1:length(X_set)-1
    %incline of the wall
    xn = x((X_set(i,2)>=x)&(x>=X_set(i,1))&(Y_max>=y)&(y>=Y_min));
    yn = y((X_set(i,2)>=x)&(x>=X_set(i,1))&(Y_max>=y)&(y>=Y_min));
    un = u((X_set(i,2)>=x)&(x>=X_set(i,1))&(Y_max>=y)&(y>=Y_min));
    vn = v((X_set(i,2)>=x)&(x>=X_set(i,1))&(Y_max>=y)&(y>=Y_min));
    Tn = T((X_set(i,2)>=x)&(x>=X_set(i,1))&(Y_max>=y)&(y>=Y_min));
    Pn = P((X_set(i,2)>=x)&(x>=X_set(i,1))&(Y_max>=y)&(y>=Y_min));

    vn_up(:,:,i) = griddata(xn,yn,vn,Mx_up(:,:,i), My_up(:,:,i),'cubic');
    un_up(:,:,i) = griddata(xn,yn,un,Mx_up(:,:,i), My_up(:,:,i),'cubic');
    Tn_up(:,:,i) = griddata(xn,yn,Tn,Mx_up(:,:,i), My_up(:,:,i),'cubic');
    Pn_up(:,:,i) = griddata(xn,yn,Pn,Mx_up(:,:,i), My_up(:,:,i),'cubic');

    
    %decline of he wall
    if i<13
    xn = x((X_set(i+1,1)>=x)&(x>=X_set(i,2))&(Y_max>=y)&(y>=Y_min));
    yn = y((X_set(i+1,1)>=x)&(x>=X_set(i,2))&(Y_max>=y)&(y>=Y_min));
    un = u((X_set(i+1,1)>=x)&(x>=X_set(i,2))&(Y_max>=y)&(y>=Y_min));
    vn = v((X_set(i+1,1)>=x)&(x>=X_set(i,2))&(Y_max>=y)&(y>=Y_min));
    Tn = T((X_set(i+1,1)>=x)&(x>=X_set(i,2))&(Y_max>=y)&(y>=Y_min));
    Pn = P((X_set(i+1,1)>=x)&(x>=X_set(i,2))&(Y_max>=y)&(y>=Y_min));


    vn_down(:,:,i) = griddata(xn,yn,vn,Mx_down(:,:,i), My_down(:,:,i),'cubic');
    un_down(:,:,i) = griddata(xn,yn,un,Mx_down(:,:,i), My_down(:,:,i),'cubic');
    Pn_down(:,:,i) = griddata(xn,yn,Pn,Mx_down(:,:,i), My_down(:,:,i),'cubic');
    Tn_down(:,:,i) = griddata(xn,yn,Tn,Mx_down(:,:,i), My_down(:,:,i),'cubic');
    end

end

Answer 1

[Abhimenyu]

Hi Ran,

I understand you want to smoothen the ripples in the attached figure. Here are a few smoothening techniques you can follow to achieve this:

• Increase the resolution of the interpolation: You can increase the number of “desired_columns” to increase the resolution as it makes the grid finer.
• Using a different interpolation method: You can use other methods of interpolation other than “cubic” like “linear” or “nearest” to address the irregularities.
• Smoothing functions: You can use various functions like “smoothdata” or “smooth” to reduce noise in the interpolated temperature values before plotting them.

For more information on different interpolation techniques, “smooth” and “smoothdata” functions, refer to the below links respectively:

1. https://www.mathworks.com/help/matlab/ref/griddata.html
2. https://www.mathworks.com/help/curvefit/smooth.html
3. https://www.mathworks.com/help/matlab/ref/smoothdata.html

I hope this helps!

Thank you,

Abhimenyu.