[iamdesperate]

Hi i am trying to run a simulation for a pipeline with natural gas that is injected with H2 (vertical pipe).

The simulation runs fine when i am not using udf (so the mesh and setup, initialization etc are okay i guess). As soon as i try to load udfs problems occur.

I have one c file that has the 4 equations i need. The first problem occurs when i press build:

Error: The UDF library you are trying to load (C:\Users\evipa\Desktop\8\Sim_files\dp0\FFF\Fluent \libudf) is not compiled for 3d on the current platform (win64).\n\nThe system cannot find the file specified.
\n\nC:\Users\evipa\Desktop\8\Sim_files\dp0\FFF\Flu ent\C:\Users\evipa\Desktop\8\Sim_files\dp0\FFF\Flu ent\libudf\win64\3d\libudf.dll
Error Object: #f

(I make sure to delete the previous udf in the library before building again)

Despite the message, when i go to manage it shows the udf, so i can load it.

Then i put the udf in the materials i use (at the fluid and mixture folder), and do initialization again (haven't changed anything else from the original simutalion that run without udf).

Then i keep seeing the same 2 errors over and over again:

reversed flow in 5 faces on pressure-outlet 9.
# Divergence detected in AMG solver: species-0 -> Increasing relaxation sweeps!
# You may try the enhanced divergence recovery with (rpsetvar 'amg/protective-enhanced? #t)
--------------------------------------------------------------------------------------
Error: Divergence detected in AMG solver: species-0

Error: Divergence detected in AMG solver: species-0
Error Object: #f




Any idea on what to do? I keep thinking that the problem is because of the compile but idk how to fix it.

Thanks in advance.
Yours truly,
A desperate student

[CFDKareem]

Can you post the UDF you are using?

[iamdesperate]

/************************************************** *******************
UDF that simulates solidification by specifying a temperature-
dependent viscosity property
************************************************** ********************/
#include "udf.h"
#include "global.h"
DEFINE_PROPERTY(cell_density,c,t)
{

real pop = C_P(c,t);
real P_op = RP_Get_Float("operating-pressure");
real p = (pop+P_op)/100000;
real rho;
real tr1=289.15;
rho = 1/(-1.076443E-03*(tr1/p)+3.989515E-05*(pow(tr1,2)/p)-4.436841E-05*tr1-6.637080E-08*(pow(tr1,3)/p)+3.012561E-08*tr1*p+1.096540E-07*pow(tr1,2));

return rho;
}
DEFINE_PROPERTY(cell_density_H2,c,t)
{
real tr1 = 289.15;
real pop = C_P(c,t);
real P_op = RP_Get_Float("operating-pressure");
real p = (pop+P_op)/100000;
real rho_H2;
rho_H2 = 1/(0.04168135*tr1/p-3.2589E-06*pow(tr1,2)/p+4.2802E-05*tr1+5.9524E-09*pow(tr1,3)/p+6.8998E-09*tr1*p-6.2674E-08*pow(tr1,2));

return rho_H2;
}
DEFINE_PROPERTY(cell_viscosity,c,t)
{

real pop = C_P(c,t);
real P_op = RP_Get_Float("operating-pressure");
real p = (pop+P_op)/100000;
real tr1=289.15;
real mu;
mu = 20.08-20.78*tr1+7.5001*p+9.752*pow(tr1,2)+0.46572*pow(p, 2)-4.7141*tr1*p;

return mu;
}
DEFINE_PROPERTY(cell_viscosity_H2,c,t)
{
real tr1 = 289.15;
real pop = C_P(c,t);
real P_op = RP_Get_Float("operating-pressure");
real p = (pop+P_op)/100000;
real mu_H2;
mu_H2= 1.9849+0.0256045*tr1+0.003971*p-0.0000081*pow(tr1,2)+0.000005944*pow(p,2)-0.0000112275*tr1*p;


return mu_H2;
}
DEFINE_PROPERTY(cell_cond,c,t)
{
real temp = 289.15;
real pop = C_P(c,t);
real P_op = RP_Get_Float("operating-pressure");
real p = pop+P_op;
real cond;
cond= (0.02003+0.000038*temp+0.000146E-5*p);
return cond;
}
DEFINE_PROPERTY(cell_cond_H2,c,t)
{
real temp = 289.15;
real pop = C_P(c,t);
real P_op = RP_Get_Float("operating-pressure");
real p = pop+P_op;
real cond_H2;
cond_H2= (0.049722+0.000460*temp+0.000074E-5*p);
return cond_H2;
}