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QuocHung_Phan November 4, 2012 09:29

UDF - Error while Solution Initialization
hello everyone,
After building and loading udf mixedbc.c when i initialize it gives the following 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: #f

i used this udf there is problem while initialization
/************************************************** *************************/
/* Implementation of the mixed boundary condition for a UDS (or multiple): */
/* q = hC ( phi - PHI_inf ) */
/************************************************** *************************/

#include "udf.h"
#include "sg.h" /* needed for the secondary gradient source macro */

/* Names of the user-defined scalar to be used */

DEFINE_PROFILE(scalarMixedBC, thread, nv)
/* constants must be specified correctly for the mixed BC */
real hC, PHI1_inf;

/* ==================== */

face_t f;
real A[ND_ND], dG[ND_ND], dr0[ND_ND], es[ND_ND], dr, A_by_es;
real Af;
real beta0, gamma;
real temp1, temp2;

Thread *t0=thread->t0;

begin_f_loop(f, thread)

/* identify the cell thread adjacent to the face thread f */
cell_t c0 = F_C0(f, thread);

BOUNDARY_FACE_GEOMETRY(f, thread, A, dr, es, A_by_es, dr0);
gamma=C_UDSI_DIFF(c0, t0, phi1);

if (NULLP(T_STORAGE_R_NV(t0, SV_UDSI_G(phi1))))
beta0=0; /* if gradient is not allocated and stored yet, bypass
the following macro (it happens when case/data files are being read */
BOUNDARY_SECONDARY_GRADIENT_SOURCE(beta0, SV_UDSI_G(phi1),dG, es, A_by_es, gamma);

/* temporary variables used in the profile expression */

F_PROFILE(f, thread, nv)
= (temp1*C_UDSI(c0, t0, phi1)- beta0 + temp2*PHI1_inf)/(temp2 + temp1);
end_f_loop(f, thread)


Can anybody help me please?

tinhtt October 11, 2013 02:59

Hi Quoc Hung,
Access_violation usually happened when the indexes of called variables are handled not correctly.
If your problem still remains, I recommence you to refer an example my_uds_flux on page 197 of UDF Manual Guide, Ansys Fluent V14.

tinhtt October 11, 2013 03:03

or resolution for same error on forum

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