[alex2293]

Hello everyone,

I want to simulate humid air condensing on a cold surface. I'm using the VOF multiphase model with Lee condensation-evaporation model.

I'm trying to write my first UDF to define the saturation temperature of humid air in the Lee model based on the C_VOF of water vapor, the water vapor density, the C_VOF of air, the air density and the temperature.

I tried to follow this thread: UDF for volume fraction

#include "udf.h"
#define rho_water_vapor 0.59;
#define rho_air 1.2;
#define mix_pressure 101325;
DEFINE_PROPERTY(saturation_temperature,c,t)
{
real sat_temp;
real partial_vapor_pressure;
cell_t cell;
Thread **pt;
Thread *cell_threads;
Domain *mixture_domain;
{
mp_thread_loop_c(t, mixture_domain, pt)
{
begin_c_loop(cell,pt)
{
real temp = C_T(cell,pt[0]);
real VOF_air = C_VOF(cell,pt[2]);
real VOF_water_vapor = C_VOF(cell,pt[2])
w = (VOF_water_vapor*rho_water_vapor)/(VOF_air*rho_air);
sat_temp = w*0.008-0.14;
}
end_c_loop(cell,pt)
}
return sat_temp;
}
}

I'm getting parse error on line 21. I think that the domain 1 is the mixture level, 1 is the air phase and 2 is the water vapor phase. However I'm not sure how to use mp_thread_loop_c and C_VOF.

Do you have any tips for me?

Alex