[fluentuser10000]

Hello,

I want to use a criteria in my UDf for mass transfer so that if the O2 concentration is more than saturation the mass transfer is zero other wise it uses a formula to calculate mass transfer, Can anyone tell me if what I am doing is correct?


real m_lg;

DEFINE_MASS_TRANSFER(kl_my2, cell, thread, from_index, from_species_index, to_index, to_species_index)
{

cell_t c;

Thread *liq= THREAD_SUB_THREAD(thread, to_index);


m_lg = 0.0;

if ( C_YI(c,liq,to_species_index) < 0.00009379)
{
m_lg = ((0.4)*0.0000443846*pow(C_D(c,thread)*C_R(c,liq)/C_MU_EFF(c,liq), 0.25));
}
else
{
m_lg= 0.0;
}
end

C_UDMI(c,thread,0)=m_lg;


return m_lg;
}


I get an error: undeclared variable for the part where I use C_YI, I do not know why?

Thanks,
St