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May 15, 2013, 23:43 
Beginner having trouble with UDF

#1 
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Hello, I am learning FLUENT and I am trying to practice creating UDFs.
I was trying to create a UDF that would create a parabolic xvelocity boundary profile on an inlet that is parallel to the yaxis. There is an example like this on the UDF manual, but it requires the inlet to be centered at y = 0. I decided to create one that would work for an inlet that is located anywhere. Here is what I have: #include "udf.h" DEFINE_PROFILE(inlet_x_velocity_profile, t, i) { real x[ND_ND]; /*2D or 3D?*/ real y_max; real y_min; real y_check, h, midpoint; int n; face_t f; Node *node; y_max = 1000000; y_min = 1000000; begin_f_loop(f,t) /*Loop through all faces of face thread */ { f_node_loop(f,t,n) /* Loop through all nodes in face, n is node number */ { node = F_NODE(f,t,n); /*get current node */ y_check = NODE_Y(node); /*real y coordinate of node*/ if (y_check > y_max) { y_max = y_check; } if (y_check < y_min) { y_min = y_check; } } } end_f_loop(f,t); h= y_maxy_min; midpoint = (y_max+y_min)/2; begin_f_loop(f,t) { F_CENTROID(x,f,t); y=x[1]; y_p = ymidpoint; F_PROFILE(f,t,i) = 1y_p*y_p; } end_f_loop(f,t); } However I keep getting this error when I try to interpret the function on FLUENT: node definition shadows previous definition Error: C:\\Users\\USER\\Desktop\\ANSYS Practice\\parabolic_velocity_profile.c: line 24: type_size: don't know what to do with TYPE_STRUCT Error: C:\\Users\\USER\\Desktop\\ANSYS Practice\\parabolic_velocity_profile.c: line 24: structure reference not implemented Any help would be really appreciated. Thank you! Last edited by owenmeanie; May 16, 2013 at 00:35. 

May 15, 2013, 23:53 

#2 
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f_node_loop(f,t) /* Loop through all nodes in face, n is node number */
Where is the "n" referred in the comment? Please change to f_node_loop(f,t, n) 

May 16, 2013, 00:34 

#3  
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Quote:
Thank you for your reply! I actually had it there but for some reason removed it before copying the code to post the thread. The message appeared before I took it out, and it still appears now that I put it back in. Sorry about that! 

May 16, 2013, 01:15 

#4 
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Try compiling your UDF file rather than interpreting.


May 16, 2013, 15:55 

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