[KaushalSumaria]

Hi,
I have a rectangular domain of helium inside which I have a semicircle domain of Zirconium. I want to mesh the whole domain with a grid. I want to initialize volume fraction of Zirconium using DEFINE_INIT udf which gives volume fraction of 1 to Zirconium in the semicircle area. I am using the following code and interpreting the UDF. However, it initializes whole domain with Zirconium. Please help. Do i need to use DEFINE_INIT udf before initialization of after? Should I use interpreted or compiled UDF?

Code: (phase id of Zirconium=3)
#include "udf.h"

/*domain pointer passed by INIT function is mixture domain*/
DEFINE_INIT(vof_init, mixture_domain)
{
int phase_domain_index;
cell_t cell;
Thread *cell_thread;
Domain *subdomain;
real xc[ND_ND];

/*loop over all subdomain(phases) in the superdomain(mixture)*/
sub_domain_loop(subdomain, mixture_domain, phase_domain_index)
{
/*loop if secondary phase=zicronium*/
if(DOMAIN_ID(subdomain)==3)

/*loop over all cell threads in the secondary phase domain*/
thread_loop_c(cell_thread, subdomain)
{
/*loop over all cells in secondary phase cell threads*/
begin_c_loop_all(cell, cell_thread)
{
C_CENTROID(xc, cell, cell_thread)
if (sqrt(ND_SUM(pow(xc[0],2), pow(xc[1],2), pow(xc[3],2)))<1.25)
/*set volume fraction to 1*/
C_VOF(cell, cell_thread)=1;
else
/*set volume fraction to 0*/
C_VOF(cell, cell_thread)=0;
}
end_c_loop_all(cell, cell_thread)
}
}
}