[nikiii]

Hi,
I solved a UDS for voltage.
Now I am trying to obtain the derivative of voltage by writing this UDF:
# include "udf.h"
# define domain_ID 1
DEFINE_ON_DEMAND(store_gradient)
{
Domain *domain;
cell_t c;
Thread *t;
domain=Get_Domain(1);
thread_loop_c (t,domain)
{
begin_c_loop (c,t)
{
C_UDMI(c,t,0) = NV_MAG(C_UDSI_G(c,t,0));
}
end_c_loop (c,t)
}
}
It compiled successfully, but when I display the contour of UDM, in all the domain it has magnitude zero!!!
What's the wrong
Thank you for advising me.

[shashank312]

What is the UDS equation you are solving?

[rou]

Hello,I have a problem with UDF
in fluent a message appear:
Error:
FLUENT received fatal signal (ACCESS_VIOLATION)
1. Note exact events leading to error.
2. Save case/data under new name.
3. Exit program and restart to continue.
4. Report error to your distributor.
Error Object: ()
can any one help me

[shashank312]

Post your UDF here and folks will take a look.

[nikiii]

hi;
thank you for your attention.
but i solved my problems.
dear rou after compiling your UDF you must press enter in fluent page then type solve/set/expert and press enter. you must type yes in front of the second text "keep temporary solver memory from being freed?". after it you can execute on demand.
good luck.

[rou]

hi,
thank you for your help nikiii but when I initialize the program it write no UDF
I don't know what's the problem?