[Zohud]

Dear all; i am studying the heat transfer of nanorefrigerant in horizontal tube under heat flux constant; but i need a method for calculate the bulk temperature of fluid for every points on axes x. I am trying write udf but there is an error

/************************************************** ********************
UDF for calculate the bulk temperature
************************************************** ********************/

#include "udf.h"


DEFINE_Tb(Tbulk,thread,temp)
{
real Tb;
real x[ND_ND]; /* this will hold the position vector */
real y[ND_ND];
real u=f_U(f,t)
real temp = F_T(face, thread); /* get face temperature */

face_t f;

begin_f_loop(face,thread) /* loops over all faces in the thread passed
in the DEFINE macro argument */
{
Tb = SUM u*temp*y / SUM u*y;
}
end_f_loop(face,thread)
}

Please help me

[Zohud]

Dear all; No one can help me? Please I need your helps

[KevinZ09]

Well, perhaps specify more clearly what the error is so people on here can help you better. Looking at your UDF, I can see multiple errors:

- What's DEFINE_Tb? Never heard of that macro. You can't just create your own macro's; you need to stick to those provided by Fluent.
- You're referencing variables like face, f, t that are either not defined at all, or defined after using them.
- What is this supposed to do: Tb = SUM u*temp*y / SUM u*y;

I'd strongly suggest first looking in Fluent's UDF manual to get a better understanding of what they do and how to use them. And also look up for information on C programming. That alone should help you solve many of the errors you get.

[Zohud]

Thank you Kevin for the comment