[DrMaMad]

I have written this Udf for an unsteady problem to compute mass rate into two walls; (without any error was compiled)
But when I was starting to calculate, I couldn't understand why Fluent crashed and closed.


thank you in advanced
i need any help


#include "udf.h"
DEFINE_EXECUTE_AT_END(Each_Timestep_Massrate) //after each step run
{
FILE *data;//folder to save data
Domain *d;
Thread *tg;//face thread glass wall
Thread *tw;//race thread water boundary
Thread *threadg;//cell thread near glass
Thread *threadw;//cell thread near water
face_t fw;
face_t fg;
cell_t cellg;
cell_t cellw;
real timestep, rateg, ratew, Fluxg, Fluxw;
real F_YIg, C_YIg, glass_T, glass_P, diffg, densg, dsg, Ag_by_es;
real F_YIw, C_YIw, water_T, water_P, diffw, densw, dsw, Aw_by_es;
real xcfg[ND_ND], xccg[ND_ND], dsgv[ND_ND], Ag[ND_ND],
esg[ND_ND];
real xcfw[ND_ND], xccw[ND_ND], dswv[ND_ND], Aw[ND_ND],
esw[ND_ND];
real delphig[ND_ND]={0.,0.};
real delphiw[ND_ND]={0.,0.};
timestep = RP_Get_Real("flow-time")/10;
d = Get_Domain(1);
rateg = 0.;
ratew = 0.;
Fluxg = 0.;
Fluxw = 0.;
tg = Lookup_Thread(d,5);
tw = Lookup_Thread(d,8);
begin_f_loop(fg,tg)
{
cellg=F_C0(fg,tg);
threadg = THREAD_T0(tg);
F_CENTROID(xcfg,fg,tg);
C_CENTROID(xccg,cellg,threadg);
NV_VV(dsgv, =, xcfg, -, xccg);
dsg=NV_MAG(dsgv);
F_AREA(Ag,fg,tg);
if (dsg != 0.)
{
esg[0]= dsgv[0]/dsg;
esg[1]= dsgv[1]/dsg;
Ag_by_es=NV_DOT(Ag,Ag)/NV_DOT(Ag,esg);
}
else
{
NV_VV(esg, =, dsgv, -, dsgv);
Ag_by_es=0.;
}
F_YIg= F_YI(fg,tg,0);
C_YIg= C_YI(cellg,threadg,0);

delphig[0]=C_YI_G(cellg,threadg,0)[0];
delphig[1]=C_YI_G(cellg,threadg,0)[1];
glass_T=F_T(fg,tg);
glass_P=F_P(fg,tg) + 101325;
if (glass_P < 101325)
glass_P = 101325;
if (glass_P > 1013250)
glass_P = 1013250;
if (glass_T < 300)
glass_T = 300;
if (glass_T > 400)
glass_T = 400;
diffg = 2.6e-5 * (101325/glass_P) * pow((glass_T/298), 1.5);
if (NNULLP(THREAD_STORAGE(tg,SV_DENSITY)))
densg = F_R(fg,tg);
else
densg = C_R(cellg,threadg);
Fluxg=densg * ((diffg*(F_YIg-C_YIg)/dsg*Ag_by_es)+(diffg*
((NV_DOT(delphig,Ag))+(Ag_by_es*NV_DOT(delphig,esg )))));
rateg += Fluxg;
}
end_f_loop(fg,tg)
begin_f_loop(fw,tw)
{
cellw=F_C0(fw,tw);
threadw = THREAD_T0(tw);
F_CENTROID(xcfw,fw,tw);
C_CENTROID(xccw,cellw,threadw);
NV_VV(dswv, =, xcfw, -, xccw);
dsw=NV_MAG(dswv);
F_AREA(Aw,fw,tw);
if (dsw != 0.)
{
esw[0]= dswv[0]/dsw;
esw[1]= dswv[1]/dsw;
Aw_by_es=NV_DOT(Aw,Aw)/NV_DOT(Aw,esw);
}
else
{
NV_VV(esw, =, dswv, -, dswv);
Aw_by_es=0.;
}
F_YIw= F_YI(fw,tw,0);
C_YIw= C_YI(cellw,threadw,0);
//delphiw=C_UDMI(cellw,threadw,0);
delphiw[0]=C_YI_G(cellw,threadw,0)[0];
delphiw[1]=C_YI_G(cellw,threadw,0)[1];
water_T=F_T(fw,tw);
water_P=F_P(fw,tw) + 101325;
if (water_P < 101325)
water_P = 101325;
if (water_P > 1013250)
water_P = 1013250;
if (water_T < 300)
water_T = 300;
if (water_T > 400)
water_T = 400;
diffw = 2.6e-5 * (101325/water_P) * pow((water_T/298), 1.5);
if (NNULLP(THREAD_STORAGE(tw,SV_DENSITY)))
densw = F_R(fw,tw);
else
densw = C_R(cellw,threadw);
Fluxw=densw * ((diffw*(F_YIw-C_YIw)/dsw*Aw_by_es)+(diffw*
((NV_DOT(delphiw,Aw))+(Aw_by_es*NV_DOT(delphiw,esw )))));
ratew += Fluxw;
}
end_f_loop(fw,tw)
data=fopen("D:\\desktop\\simulation\\Ansys\\Gaurav 6\\GauravFluent6_files\\dp0\\FFF-10\\Fluent\\MASSRATE.txt","a");
fprintf(data,"time-step evaporation-rate condensation-rate\n");
fprintf(data,"%f\t%e\t%e\n",timestep,ratew,rateg);
fclose(data);
}

[DrMaMad]

this problem is about a trapizoidal 2d planar domain which has 4 walls: UDF computes diffusive mass flux in two of these walls called glass and water