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Mahboobe365 June 14, 2013 21:09

connecting two lines
 
dear all, I wan to write udf to connect to lines together. I am going to define the temperature of line one equals to temperature of line two. one of the line belongs to the solid parts and the other belongs to fluid part. I can not use form new part, since I want to define line two as velocity inlet. can any one help me please?

Pouria June 15, 2013 13:48

Could not undrestand the problem
 
Hi,

I could not fully understand what the problem is. Can you provide some image here and explain the problem based on that?

Thank you.

Pouria

Mahboobe365 June 15, 2013 17:41

image
 
1 Attachment(s)
I have uploaded the picture. I should add this point that I have created the geometries in design modeler . so I have two bodies and in fact I have two lines for the interface. I am set the temperature of these lines equal. I have written the udf for boundary condition. As a test I have defined a linear temperature for the line belongs to vapor chamber(lets call it inlet) and write another udf for the line belongs to the solid(wall) in order to set its temperature equals to the inlet, but the temperatures will not be exactly equal

Pouria June 15, 2013 18:05

The other thing you can try is to use a DEFINE-ADJUST macro to calculate the temperature at the inlet (or wall) at the beginning of each iteration. Then you can pass the calculated temperature to DEFINE_PROFILE macro to set the temperature at the Wall (or Inlet).

Thank you.

Pouria.

Mahboobe365 June 15, 2013 18:17

1 Attachment(s)
thank you very much. My udf for the inlet is :
DEFINE_PROFILE(tempif_profile,t,i)
{

real x[ND_ND],d[10000];
face_t f;
int k;

real hfg=4237.;

Domain*d1 = Get_Domain(1);
int IDif=13;
Thread *tfif = Lookup_Thread(d1,IDif);
Thread *tc;
cell_t c;



begin_f_loop(f,t)
{


F_PROFILE(f,t,i) =1./( 1./818-(.361/hfg)*log(((F_P(f,t)+1300.))/1300.));


end_f_loop(f,t)

and for the solid wall is:
DEFINE_PROFILE(tempis_profile,t,i)
{

real x[ND_ND]; double d[10000];
face_t f,f1;
int k,N;


int IDif=13;
int IDis=14;
Domain*d1 = Get_Domain(1);
Thread *tfif = Lookup_Thread(d1,IDif);
k=-1;

begin_f_loop(f,tfif)
{

k=k+1;
d[k]=F_T(f,tfif);


}
end_f_loop(f,tfif)
N=k;
k=-1;
begin_f_loop(f,t)
{
k=k+1;

F_PROFILE(f,t,i) =d[N-k];


}
end_f_loop(f,t)

}


}

the main problem is that without defining array d , my trend would be switched . I mean for example if my temperature for inlet is T=10*x
then the resulting temperature for solid would be T=10*(L-x)!
Even by defining array d and sorting the array , some points will be switched like the picture attached to this comment, Do you think by using adjusting macros this problem will be solved? I also have to use these two tempretures to obtain heat fluxes and calculate the velocity for inlet.

Mahboobe365 June 17, 2013 11:28

Hi again,

I have no idea how to use DEFINE-ADJUST macro, would you please help meee?


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