[rossyd89]

Hi,

I need to write a UDF for temperature dependent emissivity in a continuous annealing rig. However i get this warning when building,
udf_names.c : warning C4113: 'void (*)()' differs in parameter lists from 'void (*)(void)'
it then loads without error, but when initialising i receive these errors,
Error: received a fatal signal (Segmentation fault).
Error Object: #f
I'm really struggling any help would be appreciated.

Ross

[cp703]

Hey Ross, I'm encountering this exact situation. Did you ever figure out what the problem was?

[macfly]

Hi,

For some reason (bug?), you have to run the model with a constant external emissivity first. Then you set the external emissivity to 'my_emissivity':

#include "udf.h"
DEFINE_PROFILE(my_emissivity,t,i)
{
	real tempe;
	face_t f;
	
	begin_f_loop(f,t)
		{
		tempe = F_T(f,t);
		F_PROFILE(f,t,i) = 2.54e-4*tempe;
		}
	end_f_loop(f,t)
}

P.S. don't use 'temp' as a variable name because it overrides a previous definition in Fluent

[rasoul]

hello,how do I write non bosinesq for simulation of free convection of water?
I need for udf file,please help me

[Oula]

Hi everyone

In my model there are some boundaries (walls) that their emissivities change with temperature. For example

at a specific wall
at T=200 C emissivity = 0.80
T=400 C emissivity = 0.82
T=600 C emissivity = 0.84

How can I write the suitable UDF for this case?

Any help is much appreciated