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Calculating the centre of a surface

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Old   October 17, 2012, 12:11
Default Calculating the centre of a surface
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I need to find centroid of multiple boundaries to implement in equation in UDF. I want Fluent to calculate the coordinates (x,z) of the centroid. I have written a code for area weighted centroid. I am getting an error. Can someone tell me what am I doing wrong?
( I think its with the A(). I need to calculate area in xz planes. Is it right?)

/* Calculating the centroid of the Boundary*/
begin_f_loop(f, thread)
{
F_CENTROID(p,f,thread);
F_AREA(A,f,thread);
a = (p[0]*A[1])+a;
b= (p[2]*A[1])+b;
}
end_f_loop(f, thread)

begin_f_loop(f, thread)
{
F_AREA(A,f,thread);
d = A[1] + d;
}
end_f_loop(f, thread)
k=a/d;l=b/d;

Last edited by victoryv; October 17, 2012 at 16:59.
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Old   October 17, 2012, 19:27
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Syavash
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Quote:
Originally Posted by victoryv View Post
I need to find centroid of multiple boundaries to implement in equation in UDF. I want Fluent to calculate the coordinates (x,z) of the centroid. I have written a code for area weighted centroid. I am getting an error. Can someone tell me what am I doing wrong?
( I think its with the A(). I need to calculate area in xz planes. Is it right?)

/* Calculating the centroid of the Boundary*/
begin_f_loop(f, thread)
{
F_CENTROID(p,f,thread);
F_AREA(A,f,thread);
a = (p[0]*A[1])+a;
b= (p[2]*A[1])+b;
}
end_f_loop(f, thread)

begin_f_loop(f, thread)
{
F_AREA(A,f,thread);
d = A[1] + d;
}
end_f_loop(f, thread)
k=a/d;l=b/d;
The problem is right here, if you want to access Area magnitude of a boundary face, you have to implement this macro:
area=NV_MAG(A);
instead of "A[1]"
Goodluck
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