[typhoon1010]

Hi,

I am new about udf. I am trying to write UDF which is related to thermal diffusivity. (Local Thermal Non-Equilibrium Model / Solid state energy equation)

This is code. I try to define material panel and it did not run. I did not understand UDS's logic.

My question are

1 - How can I define Ts (Solid State Temperature)
2 - What does if (i==TS) mean

I would be glad if you help.

# include "udf.h"
# define zeta 0.38
# define TKS 16.591

DEFINE_DIFFUSIVITY (uds_diffusivity, cell, thread, i)
{
real source,Ts;
if (i == TS)//if solid state temperature
{
/*source = (1-porosity)* (Thermal conductivity of solid)*/
source = ((1-zeta)*TKS);
}
else source = 0.0;
return source;
}

[nvarma]

You need to get the cell or face temperature into a variable.

like T=F_T() or C_T() (refer manual)

then compare this with TS (solid state temp) which you have to define using #define.

The code has some syntax and semantic errors. (TS not defined anywhere, i==TS doesn't make sense at all)

Refer udf manual and look at the examples there.

[typhoon1010]

This code run. But When I can define solid state temperature (#define Ts something). It did not run.

Do u know How can I define solid state temperature.

#include "udf.h"
#define TKS 10
#define SOLID_THERMAL_COND(Ts) 2
#define SOLID_DENSITY(Ts) 3
#define SOLID_CP(Ts) 2



enum { SOLID_TEMP };

DEFINE_DIFFUSIVITY( uds_diffusivity, cell, thread, i )
{

real source;
real Ts;

if (i == SOLID_TEMP)

{

Ts = C_UDSI(cell, thread, SOLID_TEMP);

source = (SOLID_THERMAL_COND(Ts) / (SOLID_DENSITY(Ts)*SOLID_CP(Ts)));

}

else source = 0.0;

return source;
}