[Ahmed A. Serageldin]

My UDF works well with Fluent 16 but did not works well with Fluent 19.
Is there any modification I have to do with my UDF or any setting in Fluent 19?
I attached The UDF to your consideration
#include "udf.h"

#define m 17
#define cp 4182

real Q[8761];
real avetempa=288.15;

DEFINE_ON_DEMAND(read_data)
{
int i;
real b;
FILE *rfile; /* declare a FILE pointer */
#if RP_HOST
host_to_node_sync_file("test.dat");
#endif
#if RP_NODE
host_to_node_sync_file("/");
#endif
rfile = fopen("data.txt", "r"); /* open file for reading */
#if RP_HOST
Message("file opened\n");
#endif
for (i=0;i<8760;i++)
{
fscanf(rfile, "%f\n", &b); /* that supposes one value per line */
Q[i]=b;
}
fclose(rfile);
#if RP_HOST
Message("file closed\n");
#endif
}

/* Defining outlet temperature.*/
DEFINE_ADJUST(average_exit_temp,domain)
{
real tempa=0.0;
real totalarea=0.0;
int ID1 = 4;//'108; /* the outlet boundary condition identifier*/
int ktt=N_TIME-1;

#if !RP_HOST
face_t f1;
real A[ND_ND];
Thread *outlet_thread = Lookup_Thread(domain,ID1);

begin_f_loop(f1,outlet_thread)
{
if PRINCIPAL_FACE_P(f1,outlet_thread)
{
F_AREA(A,f1,outlet_thread);
totalarea +=NV_MAG(A);
tempa +=NV_MAG(A)*F_T(f1,outlet_thread);
}
}
end_f_loop(f1,outlet_thread)

#if RP_NODE
tempa = PRF_GRSUM1(tempa);
totalarea = PRF_GRSUM1(totalarea);
#endif

avetempa= tempa/totalarea;
if(ktt==0) avetempa=288.15;
# endif

node_to_host_real_1(avetempa);

#if RP_HOST
Message("average temperature : %g K q7=%g\n",avetempa,Q[ktt]);
#endif
}

DEFINE_PROFILE(Inlettemp,thread,pos)
{
face_t f;
real x[ND_ND],btt;
real ftime = CURRENT_TIME;
int k_time=N_TIME;
real qheat=Q[k_time-1];

#if RP_NODE
begin_f_loop(f, thread)
{
if PRINCIPAL_FACE_P(f,thread)
{
if(ftime<1200) btt=288.15;
else btt = avetempa +((qheat-0.0000008*ftime)/(m*cp/60));
F_PROFILE(f, thread, pos) =btt;
}
}
end_f_loop(f, thread)
#endif
}

[LuckyTran]

Fluent v19 and onwards no longer supports serial mode because they want the environment to be the same from now on. A consequence is that udf's which previously only worked in serial will no longer work because there is no longer a serial mode.


You can start Fluent in serial mode by passing the -t0 flag. Launching Fluent in serial mode will actually start parallel Fluent, equivalent to the -t1 flag.


Or fix your udf. Sorry I'm too lazy to debug your udf.

[Ahmed A. Serageldin]

Originally Posted by LuckyTran

Fluent v19 and onwards no longer supports serial mode because they want the environment to be the same from now on. A consequence is that udf's which previously only worked in serial will no longer work because there is no longer a serial mode.


You can start Fluent in serial mode by passing the -t0 flag. Launching Fluent in serial mode will actually start parallel Fluent, equivalent to the -t1 flag.


Or fix your udf. Sorry I'm too lazy to debug your udf.

Thank you for kindly reply.
I used parallel fluent on Fluent 16, and this UDF is working good but when I tried it with Fluent 19 it compiled without errors, and I hooked the inlet profile and executed the read data macros but when I initialized and started calculation I found that q_time=0 and did not change with time. q_time values are stored in the data.txt file which has 8761 readings
what do you think is the wrong is it the structure of UDF or problem in Fluent 19?

[LuckyTran]

What the heck is q_time? It's not in your udf anywhere.