[Neethu_N]

Hello, please help me with this. I am studying UDF coding. I found this code in the ANSYS Manual.

/************************************************** *********************
udfexample.c
UDF for specifying steady-state velocity profile boundary condition
************************************************** **********************/
#include "udf.h"
DEFINE_PROFILE(inlet_x_velocity, thread, position)
{
real x[ND_ND]; /* this will hold the position vector */
real y, h;
face_t f;
h = 0.016; /* inlet height in m */
begin_f_loop(f,thread)
{
F_CENTROID(x, f, thread);
y = 2.*(x[1]-0.5*h)/h; /* non-dimensional y coordinate */
F_PROFILE(f, thread, position) = 0.1*(1.0-y*y);
}
end_f_loop(f, thread)
}

Is it necessary to find the centroid? The code works without it too.

[AlexanderZ]

3.2.4.1. Face Centroid (F_CENTROID)
The macro listed in Table 3.21: Macro for Face Centroids Defined in metric.h (p. 261) can be used to obtain the real centroid of a face. F_CENTROID finds the coordinate position of the centroid of the face f and stores the coordinates in the x array. Note that the x array is always one-dimensional, but it can be x[2] or x[3] depending on whether you are using the 2D or 3D solver.

[Neethu_N]

I got it. Thank you very much