[jyin]

hello everyone:

I was trying to get coordinate from the whole domain and I am successful with the following code.

#include "udf.h"

DEFINE_ON_DEMAND(on_demand)
{
real x[ND_ND],x1,y1,z1;
int ID = 2;
cell_t c;
Domain *d = Get_Domain(1);
Thread *t;



thread_loop_c(t,d)
{
begin_c_loop(c,t)
{
C_CENTROID(x,c,t);
x1 = x [0];
y1 = x [1];
z1 = x [2];
Message(" %f,%f,%f\n",x1,y1,z1);
}
end_c_loop(c,t)
}
}


But when I add the IF code to the UDF, it always comes an error in Fluent.
my goal is trying to get coordinate at gas/liquid interface. But it can not work with the following UDF. Someone can help me with this?

DEFINE_ON_DEMAND(on_demand)
{
real x[ND_ND],x1,y1,z1;
int ID = 2;
cell_t c;
Domain *d = Get_Domain(1);
Thread *t;



thread_loop_c(t,d)
{
begin_c_loop(c,t)
{
if(C_VOF(c,t)>0 && C_VOF(c,t)<1)
{
C_CENTROID(x,c,t);
x1 = x [0];
y1 = x [1];
z1 = x [2];
Message(" %f,%f,%f\n",x1,y1,z1);
}
}
end_c_loop(c,t)
}
}

[AlexanderZ]

what kind of error did you get?

may be the problem is in the brackets?

if ((C_VOF(c,t)>0) && (C_VOF(c,t)<1))

best regards