[thiyam]

I am modelling gas-liquid phase problem in fluent and trying to use UDF for drag co-efficient, in this case i want to particularly define viscosity for liquid phase so does anyone know macro for this, please help

[Galileo]

Originally Posted by thiyam

I am modelling gas-liquid phase problem in fluent and trying to use UDF for drag co-efficient, in this case i want to particularly define viscosity for liquid phase so does anyone know macro for this, please help

Hi,
To define the viscosity of the liquid phase you can do something like:

/*If the cell and cell thread are not passed in the
subrountine, you need to get the cell thread
eg for DPM Drag
DEFINE_DPM_DRAG(UDFdrag,Re,p)
where the Tracked Particle p is passed you may
do it like this
cell = P_CELL(p);
cell_thread =
THREAD_SUB_THREAD(P_CELL_THREAD(p),
PHASE_DOMAIN_INDEX (Get_Domain(ID_OF_LIQUID_PHASE)));
You can get ID_OF_LIQUID_PHASE from the phases GUI, may be 3

What is important is to get cell and cell_thread, pointing to the phase you desire
*/
viscosity_lam=C_MU_L(cell,cell_thread) //Laminar Viscosity
viscosity_turb=C_MU_T(cell,cell_thread) //Turbulent Viscosity
viscosity_eff=C_MU_EFF(cell,cell_thread) //Effective Viscosity