hi I attached udf file with interpreted method I received this error when I run "execute on demand". 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: () my udf is : # include "udf.h" DEFINE_ON_DEMAND(store_gradx) { 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) = C_T_G(c,t)[1]; } end_c_loop (c,t) } }

thanks your attention

have you defined a new memory location in the fluent UDF menu BEFORE running the execute on demand command?

Dear Phil Thank you for attention. I have defined a new memory location in the fluent UDF menu BEFORE running the Execute on demand command. Best regards

you get this error because the temperature gradient is not yet allocated. try like this:

# include "udf.h"

DEFINE_ON_DEMAND(store_gradx) { Domain *domain; cell_t c; Thread *t; domain=Get_Domain(1); thread_loop_c (t,domain) { if (T_STORAGE_R_NV(t,SV_T_G)!=NULL){ begin_c_loop (c,t) { C_UDMI(c,t,0) = C_T_G(c,t)[1]; } end_c_loop (c,t) }else Message("temperature gradient not yet allocated\n"); } }

Hi dear

I received this error when I run "execute on demand".

Error: Chip: internal error: invalid builtin -1: pc=121

Error Object: ()

best regards