[Chhotelal1234]

Hello friends,

I want to define specific heat by UDF to define solid property, for that I add this UDF code but when I add this code to specific heat property it is not added and an error is coming that does not imply a user-defined function for a specific heat.

DEFINE_PROPERTY(heat_capacity_particles, c, t)
{
real Xp, Cp_w, Cp_pd, Cp_p;

Xp = 0.25;
Cp_w = 4182;// Heat capacity of water
Cp_pd =1200; // Heat capacity of dry particle

// Calculate the heat capacity of solid particles
Cp_p = Cp_w * Xp + Cp_pd;

return Cp_p;
}

[AlexanderZ]

this part of code is ok
do you have header

#include <udf.h>

???

[Chhotelal1234]

yes, I already defined it. but it is not adding.

I also saw in the UDF manual, another specific heat function that is adding.
I want to know why my defined UDF is not added in the solid property while the code is written right.

another UDF is which is add successful
#include "udf.h"

DEFINE_SPECIFIC_HEAT(my_user_cp, T, Tref, h, yi)
{
real cp=2000.;
*h = cp*(T-Tref);
return cp;
}

[AlexanderZ]

DEFINE_SPECIFIC_HEAT macro is an answer

[Chhotelal1234]

I did not understand,

My actual UDF function is given below, specific heat change with respect to moisture Xp, what should I need to change so that I can add in the solid property?

DEFINE_PROPERTY(heat_capacity_particles, c, t)
{
real Xp, Cp_w, Cp_pd, Cp_p;

Xp = 0.25;
Cp_w = 4182;// Heat capacity of water
Cp_pd =1200; // Heat capacity of dry particle

// Calculate the heat capacity of solid particles
Cp_p = Cp_w * Xp + Cp_pd;

return Cp_p;
}

[AlexanderZ]

DEFINE_SPECIFIC_HEAT for specific heat

[Chhotelal1234]

When I defined the Specific heat function as given in the manual, we need to define T, Tref, h, and Yi
in that case, UDF compiled successfully but when I added it in the property section bed termination error is coming.
please look at my updated code.
DEFINE_SPECIFIC_HEAT(my_user_cp, T, Tref, h, yi)
{
real Xp, Cp_w, Cp_pd, Cp;
Thread *t;
cell_t c;

t = THREAD_T0(t);
begin_c_loop(c, t)
{
Xp = C_UDMI(c, t, 0); // Assuming moisture content is stored in the UDM
Cp_w = 4182; // Heat capacity of water
Cp_pd = 1200; // Heat capacity of dry particle

// Calculate the heat capacity of solid particles
Cp = Cp_w * Xp + Cp_pd;
*h = Cp * (T - Tref);

/* Print the result */
Message("specific_heat_particles: %f\n", Cp);
}
end_c_loop(c, t)

return Cp;
}