[amirkhan5997]

Hi everyone,
I am trying to compile the following UDF and it runs without the data saving part but as soon as I add this

#if RP_HOST
fp = fopen("data.txt", "a");
fprintf(fp,"%g %g %g %g %g \n",time,cg[1],vel[1],cg[2],omega[1])
fclose(fp);
#endif

it doesnt work. Any help will highly appriciated

#include "udf.h"
#include "math.h"
#include <stdio.h>

static real v_prev_y = 0.0;
static real v_prev_theta = 0.0;

DEFINE_CG_MOTION(flapping,dt,vel,omega,time,dtime)
{
Thread *t;
Domain *d;
FILE *fp;


real cg[3]; real force[3]; real moment[3];

real accl_y;
real dv_y;
real accl_theta;
real dv_theta;

real ured = 10;

real mass_y = 63.9;
real eta = 0.01;
real ro = 1.0;

real c_y = 0;
real k_y = 289.5;

real c_theta = 0.501;
real k_theta = 0;

real lambda = -0.0033;
real l_theta = 0.067;

real I_theta = 0.146 ;

int i;
NV_S(vel,=,0.0);
NV_S(omega,=,0.0);

t = DT_THREAD(dt);
d = Get_Domain(1);


cg[1]=DT_CG(dt)[1];
cg[2]=DT_THETA(dt)[2];

Compute_Force_And_Moment(d,t,cg,force,moment,TRUE);

force[1] += -k_y * cg[1] - c_y * vel[1];
moment[2] += -k_theta * cg[2] - c_theta * omega[2];

accl_y = force[1]/mass_y;
accl_theta = moment[2]/I_theta;

dv_y = accl_y * dtime;
dv_theta = accl_theta * dtime;

v_prev_y += dv_y;
v_prev_theta += dv_theta;

vel[1] = v_prev_y;
omega[2] = v_prev_theta;

#if RP_HOST
fp = fopen("data.txt", "a");
fprintf(fp,"%g %g %g %g %g \n",time,cg[1],vel[1],cg[2],omega[1])
fclose(fp);
#endif
}

[Siba11]

Hi. You should try this instead:

#if !RP_HOST
.
.
.
#endif

Also, place the #if !RP_HOST line as soon as you enter the DEFINE_CG_MOTION block.

[amirkhan5997]

I get the following after building.

Copied C:\Users\engra\OneDrive - National University of Sciences & Technology\UDFs\UDF_Passive_Flapping - Copy.c to libudf\src
Creating user_nt.udf file for 2ddp_host ...
(system "copy "C:\PROGRA~1\ANSYSI~1\v201\fluent"\fluent20.1.0\src\udf\makefile_nt.udf "libudf\win64\2ddp_host\makefile" ")
        1 file(s) copied.
(chdir "libudf")(chdir "win64\2ddp_host")Creating user_nt.udf file for 2ddp_node ...
(system "copy "C:\PROGRA~1\ANSYSI~1\v201\fluent"\fluent20.1.0\src\udf\makefile_nt.udf "libudf\win64\2ddp_node\makefile" ")
        1 file(s) copied.
(chdir "libudf")(chdir "win64\2ddp_node")
Done.

But when I load is says

Error at Node 23: The UDF library you are trying to load (libudf) is not compiled for parallel use on the current platform (win64).

The system cannot find the file specified.