[mataus]

Hai...
Here is the simplified UDF for single-phase conjugate problem. The UDF calculates some values in the solid region.
DEFINE_EXECUTE_AT_END(source_calculation)
{
Domain *d=Get_Domain(1);
int zone_id=6;
Thread *t = Lookup_Thread(d,zone_id);
cell_t c;
thread_loop_c(t,d)
...
...


How to transform this UDF for the multiphase simulation problem? I need to do the same calculation in the solid region.

I am running transient-eulerian-boling-RPI model

It shows segmentation faults after the end first-time step when I run the simulation on multiphase with the above UDF.

I checked the zone id.


Cheers,

[AlexanderZ]

not enough information

you may try to find examples on multiphase simulations in Ansys Fluent Customization manual

[mataus]

Thanks for the reply.
I can explain my simulation.
the domain consists of one solid and one fluid region.
a heat source is introduced in the solid region. the heat generated in the solid region is transferred to the flowing fluid and its temperature rises.
I have introduced a UDF( DEFINE_EXECUTE_AT_END) to calculate some values in the solid region.
the UDF works correctly and runs the simulation successfully.

#include "udf.h"
#define p 13.4
#define s 301.0024
#define m 4.12
DEFINE_EXECUTE_AT_END(pom_calculation)
{
Domain *d=Get_Domain(1);
int zone_id=6;
Thread *t = Lookup_Thread(d,zone_id);
cell_t c;
real dt=CURRENT_TIMESTEP;
thread_loop_c(t,d)
{
begin_c_loop(c,t)
{
C_UDMI(c,t,1)=C_T(c,t)/s;
C_UDMI(c,t,3)=C_T(c,t)/p;
{
if (C_UDMI(c,t,3)>C_UDMI(c,t,1))
{
C_UDMI(c,t,2)=C_T(c,t)*m;
}
else
{
C_UDMI(c,t,2)=0;
}
C_UDMI(c,t,0)=C_UDMI(c,t,0)+(C_UDMI(c,t,2)*C_T(c,t ));
}
end_c_loop(c,t)
}
}
}

later I need to introduce a phase change of fluid (liq-vap) due to the heat transfer from the solid region. I tried the same UDF but it shows segmentation fault at the end first-time step.
I successfully simulate without the UDF.

how can I edit above udf to run in multiphase flow condition?

[AlexanderZ]

code is correct

this code is not related to source, so it can't work the way, you've told
actually it does nothing

most likely, you didn't allocate memory for your user defined memories
you should put 4 in fluent GUI

[mataus]

thanks for your quick reply.
yes..you are correct the code does nothing with source term.
this is a simplified version of the UDF.
I have correctly allocated 4 memory locations.