[cfdstar]

Hi experts,

I wanted to model a gas-liquid problem using a fixed grid approach (i.e. no dynamic mesh), in which the liquid interface is heated by an external source. The free surface is free to deform and move. How can I distribute a flux over this dynamic free surface? Is there any UDF example that I can use or modify to this end?

Cheers

[doruk]

Hello,

You can use DEFINE_SOURCE macro and add it to the cell zone source terms.

here is how i would do it

DEFINE_SOURCE(Energy, cell, thread, dS, eqn)

{
real heat;
Thread *pri_th, *sec_th;
pri_th = THREAD_SUB_THREAD(thread,0);
sec_th = THREAD_SUB_THREAD(thread,1);

if(C_VOF(cell,sec_th)>0.001&&C_VOF(cell,sec_th)<0. 99) //finds the free surface
{
heat=900; // this value has to be w/m3. You can adjust this as you wish
}
else
{
heat=0;
}

dS[eqn] = 0;
return heat;

}

best regards,
Doruk