[kouroshp]

Hi guys
i am trying to simulate a constant volumetric energy source in a specific zone in my domain in fluent so all the cells within that zone would have same source energy . i wrote the below udf but the problem is temperature wouldn't increase within the zone ....i have already applied the udf to the specific zone....any idea? thanks

#include "udf.h"

DEFINE_SOURCE(energy_source,c,t,dS,eqn)
{
real x[ND_ND];
real source;
C_CENTROID(x,c,t);
source = 50000000000 ;
return source;
}

[kouroshp]

Hey Guys

I changed the udf as below but still there is no change in the temperature inside my zone, any ideas? Thanks.
#include "udf.h"

DEFINE_SOURCE(energy_source,cell,thread,dS,eqn)
{

real source;

source = 500000000.;

return source;
}

[kouroshp]

any suggestions guys? thanks

[kouroshp]

any help guys?

[macfly]

Did you try with the dS[eqn] line?

DEFINE_SOURCE(energy_source,cell,thread,dS,eqn)
{
real source;
source = 500000000.;
dS[eqn] = 0.;
return source; 
}

[kouroshp]

no it doesn't work i tried it before. i am confused , when i go to my zone in fluent and define the same value as constant parameter it works fine but when i use the above udf nothing happens. i need to do this with udf since i need to make it change with time in the next step.

Originally Posted by macfly

Did you try with the dS[eqn] line?

DEFINE_SOURCE(energy_source,cell,thread,dS,eqn)
{
real source;
source = 500000000.;
dS[eqn] = 0.;
return source; 
}

[macfly]

Have you tried with both interpreted and compiled udf?

[kouroshp]

I always interpret(not compiling) my udfs and they worked fine before .when I tried to compile this one it gave an error but I am not sure if this is the source of my problem since it interprets the udf without an error and I can choose it in my zone in fluent.
Thanks for your response .

Originally Posted by macfly

Have you tried with both interpreted and compiled udf?

[JimKnopf]

And you did specify the source term in the cell zone?

[mvee]

Your cell c and thread t should specifically refers to the zone on which you want to apply source.
You can trace the thread using lookup_thread macro.

Best wishes
Mvee

[mvee]

Again, if your source is constant value then you need not to define it through UDF. You can implement it through cell zone conditions.