problem with udf programming in fluent
 

Hi, I m new to udf programming in fluent.I have tried to write a simple program to give x component of velocity as zero using DEFINE_PROFLIE macro.My program shows no error with interpretation.But when i try to solve, the following error occurs:

Error: FLUENT received fatal signal (ACCESS_VIOLATION) 1. Note exact events leading to error. 2. Save case/data under new name. 3. Exit program and restart to continue. 4. Report error to your distributor. Error Object: ()

This is my program.

# include "udf.h"

DEFINE_PROFILE(inlet_velocity,face,t,i)
{
real y;
face_t f;
int i;

begin_f_loop(f,t)
{
y=F_U(f,t)=0;
F_PROFILE(f,t,i)=y;
}
end_f_loop(f,t)
}

Can u please help me on this?