[kookguy]

Hello,

I am new to writing UDFs for FLUENT (launched from Workbench). I am trying to interpreted a UDF source code for a tangential mass flow (compressible flow) for the first time but then I got stuck with errors.

Here is some information regarding my Fluent setting:
Version: 13.0.0
Working Directory: C:\Users\Kookguy
FLUENT ROOT Path: C:\Program Files\ANSYS Inc\v130/fluent

The following is my UDF source file, "myudfexample.c":
/************************************************** *********************
myudfexample.c
UDF for specifying swirling flow
************************************************** **********************/
#include "udf.h"
DEFINE_PROFILE(inlet_tangential_massflow, thread, position)
{
real x[ND_ND];
real y,z,r;

y=x[1];
z=x[2];
face_t f;

begin_f_loop(f,thread)
{
F_CENTROID(x, f, thread);
r=sqrt(pow(y,2)+pow(z,2)); /*acquiring radius*/
F_PROFILE(f, thread, position) = (r/0.01)*(0.5775); /*S=0.385, so (V=0.5775*U)*/
}
end_f_loop(f, thread)
}


Here are the errors I got as I interpreted the file (also shows my source file location):

Error: C:\Users\Kookguy\Desktop\ColdFlow\Sim5_try3_files\ dp0\FFF\Fluent\myudfexample.c: line 13: parse error.
Error: C:\Users\Kookguy\Desktop\ColdFlow\Sim5_try3_files\ dp0\FFF\Fluent\myudfexample.c: line 15: f: undeclared variable

where line 13, I believe is corresponded to face_t f, which causes subsequent problem in line 15.

What am I doing wrong here? Please Help!!

[GM_XIII]

Are you compiling or interpreting it?
pd: it also seems to me that x and y are always 0 check it

[gfoam]

Hi:
i think that you have to do the statements y=x[1]; and z=x[2]; after calculating 'x' in the statement F_CENTROID(x, f, thread);, otherwise you will get the initial value of X[1] and X[2] for y and z. Regards
Gonzalo

[kookguy]

Thank you very much for the comments!

GM_III, I was just interpreting the file. Do I have to compile it first? Any quick guidance of how and why to do that? Thank you very much for your help.

gfoam, I will change that!, again Thank you so much!

Hopefully, it will be all clear to me once I got the first file running; however, I'm still stuck at the moment.

[gfoam]

Hi:
I don't think you have to compile it because it's a very simple UDF and it serves only on the porpouse of initializing a BC's. But the UDF seems to bo OK if you change the statement I said to you before. Now, how are you trying to execute it? What variable type is "position" and how are you passing it to the UDF?