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UDF-reference to a different thread

Hi everybody,
I have to create a UDF for a wall: in particular the wall temperature must depend on the temperature of a point not next to the boundary (in this point there's a temperature sensor and the wall temperature changes thanks to a feedback)
I don't now how to create the thread, in the UDF, referring to this point (so that I can use C_T function...)
I should have, in the end, two threads in my UDF: the one belonging to the boundary (declared in DEFINE_PROFILE) and this new thread...
Some suggestions?
(excuse for my bad english)

Quote:

Originally Posted by Bionico (Post 336339)

Dear Flavio,

you can easily separate your desired volume which encompasses the sensor with this procedure:
1) Adapt->region ..... (define your volume as small as possible which contains the sensor location)
2) grid ->separate-> cells ..... (separate the selected volume)
3) define-> boundary condition ..... (find its ID)
4) if this volume contains more than 1 cell, do proper consideration in UDF such as finding average of properties in this volume and then use it as sensor variable...
5) Enjoy!

Bests,

Thank you very much, Amir :)
I haven't tried your solution yet because I would prefer one independent on the mesh
I have written this UDF, but it doesn't work

Code:

 

DEFINE_ADJUST(tsensor,domain)

{

 real trif_coordinate[ND_ND];

 real trif;

 real xmin;

 real xmax;

 real ymin; 

 real ymax;

 real zmin; 

 real zmax;

 real x,y,z,nt;

 

 cell_t c;

 Domain *d;

 Thread *t;

 d = Get_Domain(1);

 

 xmin=-1.940;

 xmax=-1.860;

 ymin=-1.040;

 ymax=-0.960;

 zmin=1.360;

 zmax=1.440;

 

 thread_loop_c(t,d)

 {

 nt=0.0;

 begin_c_loop(c,t)

 {

  C_CENTROID(trif_coordinate,c,t);

 

  x=trif_coordinate[0];

  y=trif_coordinate[1];

  z=trif_coordinate[2];

 

 

  if ((x >= xmin) && (x <= xmax))

  { 

   if ((y >= ymin) && (y <= ymax))

   {

    if ((z >= zmin) && (z <= zmax))

    {

     trif=trif + C_T(c,t);      

     nt=nt+1.0;       

    }

   }

  }

 }

 end_c_loop(c,t)

 }

 trif=trif/nt;

}

 

DEFINE_PROFILE(twall, thread, position)

{

 real trif;

 real tlimit;

 face_t f;

 tlimit=291.65;

 if (trif>tlimit)

 

   begin_f_loop(f,thread)

 {

     F_PROFILE(f, thread, position) = 291.15-(trif-291.15);  

 }

   end_f_loop(f, thread)

 else

   begin_f_loop(f,thread)

 {

     F_PROFILE(f, thread, position) = 291.15;    

 }

   end_f_loop(f, thread)

 

}

wall temperature doesn't decrease even if trif>tlimit :(
maybe in DEFINE_PROFILE trif isn't the one defined in the previuos function (DEFINE_ADJUST)?

Yes; use global variable for "trif"

Bests,