liquid liquid extraction - VOF
 

I am trying to do liquid liquid extraction using VOF model in a stratified flow of two immiscible liquids ( 1. mixture of toluene and acetone 2. water) I want to extract acetone from the mixture to water across the interface.



#include "udf.h"
DEFINE_MASS_TRANSFER(source, cell, mix_thread, from_index, from_species_index, to_index, to_species_index)
{
real m_lg;
Thread *pri_th, *sec_th;
pri_th = THREAD_SUB_THREAD(mix_thread, from_index);
sec_th = THREAD_SUB_THREAD(thread, to_index);
m_lg = 0.0;
if (C_VOF(cell, sec_th) != 1.0)
{
m_lg =0.00005;
}
return m_lg;
}

What macro I have to use to identify the particular species (acetone) in a mixture and transfer it across the interface.

Thanks in advance