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DEFIND_SOURCE with looping through DPM particles

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Old   October 21, 2011, 02:43
Default DEFIND_SOURCE with looping through DPM particles
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help!

I run a simulation with Discrete Phase model. The Defind_Source macro is used for the continuity, and I want to relate it with DPM particles, so how to write the UDF with Looping over the particles in the cell?
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Old   October 21, 2011, 03:55
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Hi,
Loop over all particles and check whether it is in your desired cell and thread or not with P_CELL and P_THREAD commands:

Quote:
loop over cells
{
loop over particles
{
.......
}
}
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Old   October 24, 2011, 22:00
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Quote:
Originally Posted by Amir View Post
Hi,
Loop over all particles and check whether it is in your desired cell and thread or not with P_CELL and P_THREAD commands:
dear Amir, many thanks for your reply.
A main difficult to loop over all particles in Define_Source macro is that I can't get the tracked particle thread.
My test UDF is as following:

# include "udf.h"
DEFINE_SOURCE(chg_source,c,t,dS,eqn)
{
int I=0;
real xc[ND_ND];
real source;

Tracked_Particle *p;
cell_t cell;

loop(p,I->p)
{
cell = P_CELL(p);
if (c==cell)
{
C_CENTROID(xc,c,t);
Message("P_POS(p)[0]: %g\n", P_POS(p)[0]);
Message("P_POS(p)[1]: %g\n", P_POS(p)[1]);
Message("xc[0]: %g\n", xc[0]);
Message("xc[1]: %g\n", xc[1]);
}
dS[eqn] = 0;
source = 0;
return source;
}

compiling Error is in line: loop(p,I->p)
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Old   October 25, 2011, 04:06
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Hi,

First of all, I don't think "I" is defined properly, is it integer?! But I think if there would be a problem in this procedure, it's better to change order of loops; i.e., use a DPM macro which automatically have a loop over particles; maybe "SCALAR_UPDATE" is proper; then store effect of each particle in its temporary cell memories and then use that memory in your source macro. I can elaborate it more if it's not clear.

Bests,
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Last edited by Amir; October 25, 2011 at 04:53.
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Old   November 8, 2011, 03:24
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Quote:
Originally Posted by Amir View Post
Hi,

...... i.e., use a DPM macro which automatically have a loop over particles; maybe "SCALAR_UPDATE" is proper; then store effect of each particle in its temporary cell memories and then use that memory in your source macro. I can elaborate it more if it's not clear.

Bests,
it's a good idea. I'll try it. thanks for your advice.
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