[Rhyno466]

I have written a UDF for a dynamic mesh movement. I think I have parallelized it correctly, but my output file ends up having two entries for each timestep. The worst part is that i copied a previous (simpler test) code that works and just added to it. I do not know what I am doing wrong and am hoping someone can spot the error in my code.

Code:

#include "udf.h"

DEFINE_CG_MOTION(thesis_1,dt,vel,omega,time,dtime)
{
/* Initialize the variables */
double flx = 0;
double flvx = 0;
double flvy = 0;
double fly = 0;
double ftx = 0;
double fty = 0;
double ftvx = 0;
double ftvy = 0;
double LFX = 0;
double LFY = 0;
double TFX = 0;
double TFY = 0;
double B = 0.087266463;
double Bdeg = 5;
double Rl = 0;
double Rt = 0;
double r = .7366;
double I = 50;
double t = 0;
double w = 0;
double LVX = 0;
double LVY = 0;
double LX = -0.733797015;
double LY = 0.06419892;
double V = 0;
FILE *fp;


#if !RP_HOST
Domain *d = Get_Domain(1);
Thread *t1 = Lookup_Thread(d,18);
Thread *t2 = Lookup_Thread(d,19);
face_t f;
real NV_VEC(A);
#endif

#if !RP_HOST
begin_f_loop(f,t1)
{
if PRINCIPAL_FACE_P(f,t1)
{
F_AREA(A,f,t1);
flx += F_P(f,t1) * A[0];
fly += F_P(f,t1) * A[1];
flvx += -F_STORAGE_R_N3V(f,t1,SV_WALL_SHEAR)[0];
flvy += -F_STORAGE_R_N3V(f,t1,SV_WALL_SHEAR)[1];
}
}
end_f_loop(f,t1)

begin_f_loop(f,t2)
{
if PRINCIPAL_FACE_P(f,t2)
{
F_AREA(A,f,t2);
ftx += F_P(f,t2) * A[0];
fty += F_P(f,t2) * A[1];
ftvx += -F_STORAGE_R_N3V(f,t2,SV_WALL_SHEAR)[0];
ftvy += -F_STORAGE_R_N3V(f,t2,SV_WALL_SHEAR)[1];
}
}
end_f_loop(f,t2)

# if RP_NODE
flx = PRF_GRSUM1(flx);
fly = PRF_GRSUM1(fly);
flvx = PRF_GRSUM1(flvx);
flvy = PRF_GRSUM1(flvy);

ftx = PRF_GRSUM1(ftx);
fty = PRF_GRSUM1(fty);
ftvx = PRF_GRSUM1(ftvx);
ftvy = PRF_GRSUM1(ftvy); 

# endif 
# endif 

node_to_host_real_4(ftx,fty,ftvx,ftvy);
node_to_host_real_4(flx,fly,flvx,flvy);

#if !RP_NODE
LFX = flx+flvx;
LFY = fly+flvy;
TFX = ftx+ftvx;
TFY = fty+ftvy;
Rl = LFY*cos(B) + LFX*sin(B);
Rt = TFY*cos(B) + TFX*sin(B);
t = (Rl*r) + (Rt*-r);
w += dtime * t / I;
V = w*r;
LVX = V * sin(B);
LVY = V * cos(B);
LX += LVX * dtime;
LY += LVY * dtime;
B = asin(LY/r);
Bdeg = B * (180 / 3.141592654);

if (time < 2*dtime)
    {
    fp = fopen("data.txt","a");
    fprintf(fp,"%s\t\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t\t%s\t\t%s\t\t%s\t\t%s\t\t%s\t\t%s\t\t%s\t\t%s\t\t%s\n","Time","Lead X P","Lead Y P","Lead X V","Lead Y V","Trail X P","Trail Y P","Trail X V","Trail Y V","Lead X","Lead Y","Trail X","Trail Y","Beta","Omega","LVX","LVY","LX","LY");
    fclose(fp);
    }
    
fp = fopen("data.txt","a");
fprintf(fp,"%f\t%f\t%f\t%f\t%f\t%f\t%f\t%f\t%f\t%f\t%f\t%f\t%f\t%f\t%f\t%f\t%f\t%f\t%f\t\n",time,flx,fly,flvx,flvy,ftx,fty,ftvx,ftvy,LFX,LFY,TFX,TFY,Bdeg,w,LVX,LVY,LX,LY);
fclose(fp);

Message ("\nL x Vel = %f L y Vel = %f\n", LVX,LVY);

vel[0] = LVX;     
vel[1] = LVY;
# endif


}

Output file example (columns have been excluded):

Time        Lead X P    Lead Y P    Lead X V    Lead Y V
0.001000    0.000000    0.000000    0.000000    0.000000
Time        Lead X P    Lead Y P    Lead X V    Lead Y V
0.001000    0.000000    0.000000    0.000000    0.000000
0.002000    10.623311    36.454840    0.872069    -0.048243
0.002000    10.623311    36.454840    0.872069    -0.048243
0.003000    0.466253    6.171916    0.494376    -0.022958
0.003000    0.466253    6.171916    0.494376    -0.022958
0.004000    0.472719    6.516934    0.409909    -0.016084
0.004000    0.472719    6.516934    0.409909    -0.016084
0.005000    0.483602    6.807011    0.358680    -0.011679
0.005000    0.483602    6.807011    0.358680    -0.011679

[Rhyno466]

It seems that this double printing entry occurs whether or not I am in serial or parallel mode. What would cause Fluent to look at those output lines of code twice per time step? Also, where should the vel[x] code be for this calculation?