Learning Forum

[kfouladi]

Hello All,

I have problem using a DEFINE_EXECUTE_AT_END UDF. It seems not to do anything or at least it does not create the output file (edata.txt). I originally had this UDF as a DEFINE_ON_DEMAND, which worked fine. Any help would be appreciated. 

This is what fluent writes at the end:

Registering UdfSource, ("Users/kfoul_000/Documents/…../gen.c")

Registering Udflib, ("Users/kfoul_000/Documents/…./dp0/FFF-1/Fluent/libudfxaa1")

 Writing data to C:Userskfoul_000Documents....dp0FFF-1FluentFFF-1.1.ip ...

(1) I have defined 3 User-Defined Memory. (2) Please disregard the accuracy of the equation.

My UDF file is attached to the next post.

 

Kamran

[kfouladi]

#include "udf.h"

DEFINE_EXECUTE_AT_END(gen)

{

  Domain *d; /* declare domain pointer since it is not passed as an  

                 argument to the DEFINE macro  */

   real temp = 293.15;

   real dudx, dudy;

   real rho = 1000.0;

   real sum_e;

   sum_e=0.;

   Thread *t;

   cell_t c;

   d = Get_Domain(1);     /* Get the domain using Fluent utility */

     /*(location index 0)                                            */

    /* Loop over all cell threads in the domain */

   thread_loop_c(t,d)

     {

     begin_c_loop(c,t)

       {

dudx = C_U_G(c,t)[0];

dudy = C_U_G(c,t)[1];

         C_UDMI(c,t,0) = 1.0/temp*(2*(pow(dudx,2) + pow(dvdy,2) ));

C_UDMI(c,t,1) = rho;

C_UDMI(c,t,2) = C_UDMI(c,t,0) + C_UDMI(c,t,1);

       sum_e += C_UDMI(c,t,2) * C_VOLUME(c,t);

       }

     end_c_loop(c,t)

        }

printf("Volume integral e: %gn", sum_e);

FILE *fp;    

  fp = fopen("edata.txt","w+"); 

 fprintf(fp, "Volume integral e: %gn", sum_e);

fclose(fp); 

fflush(stdout);

}

[Konstantine Kourbatski]

1) is the DEFINE_EXECUTE_AT_END executed? You have printf, is this message been printed?

2) since you are not specifying explicit path to the file, fluent is expected to open file in project_filesdp0FLUFluent, but if it's not there, do a quick search of your folders to check if it's been written in a different place

[kfouladi]

I am not sure DEFINE_EXECUTE_AT_END is executed. printf is not printed and I checked my computer and there is no "edata.txt" in any directory.

[Konstantine Kourbatski]

is it properly hooked: User-Defined - Functions - Hooks

[Konstantine Kourbatski]

Is DEFINE_EXECUTE_AT_END executed at every iteration? Do you see printf outputs after each iteration? What may happen is the file is not overwritten at a subsequent execution, but this is a basic C programming question not related to ANSYS products