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define_on_demand:Initialization of a scalar

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Old   June 28, 2017, 03:05
Smile define_on_demand:Initialization of a scalar
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How to use a define_on_demand macro to initialize a scalar in the field?
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Old   June 28, 2017, 06:47
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This is for all cells:
Code:
DEFINE_ON_DEMAND (scalar_init) 
{
  float x = 1.0; /*your value here*/
  Thread *thread;  
  cell_t cell;   
  Domain *domain = Get_Domain(1);         
  thread_loop_c(thread,domain)     
  {       
    begin_c_loop(cell,thread)              
    {       
    C_UDSI(cell,thread,0) = x;        
    }       
    end_c_loop(cell,thread)     
  }  
}
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Old   June 28, 2017, 08:45
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Thank you so much for the reply.
Actually, I am looking for assigning a constant value('0') for all the cells in a particular thread at the start of the calculation.
I wrote my UDF like this

#include "udf.h"

DEFINE_ON_DEMAND(rec)
{
Domain *d;
int zone_id=3;
Thread *t = Lookup_Thread(d,zone_id);
cell_t c;
d = Get_Domain(1);
thread_loop_c(t,d)
{
begin_c_loop(c,t)
{
C_UDMI(c,t,0) = 0;
}
end_c_loop(c,t)
}
}

Then I interpret this udf. but i dont know how to proceed further.
how can i assign the value '0' for all the cells at the beginning of calculation?
Will it assign automatically after i interpret the udf?
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Old   June 28, 2017, 09:46
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Do you have some non-zero values in UDM-0?

You have to use the DEFINE_ON_DEMAND - macro with manual command.

http://jullio.pe.kr/fluent6.1/help/h...-use-on-demand

Or you can use the Fluent patch panel:

https://www.sharcnet.ca/Software/Flu...g/node1035.htm
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Old   June 28, 2017, 09:49
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Thank you so much...
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