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Udf for moving heat flux in 2D cylindrical geometry

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Old   April 20, 2015, 01:27
Default Udf for moving heat flux in 2D cylindrical geometry
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devia
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Hello every body,
Now, I trying to analysis a heat flux in a moving electron beam melting on the cylindrical top surface of material in 2D. But I have a problem to simulate a moving heat flux on different position of material (in position 0mm, 5mm,10mm,15mm and 20mm), can you give me any suggestion for my simulation?
The simple sketch of the geometry is in attached:

This is my udf, but I didn't get the true contour.
Quote:
#include "udf.h"
DEFINE_PROFILE(EB_flux,t,i)
{
real x[ND_ND];
face_t f;
real flux;
real r;
real the_current_time;
real ti=1;
real abs = 0.75; // absorption of co
real I = 10000.0; // EB power
real sigma = 0.005;
real emis = 0.37; //emissivity
real epsilon = 0.0000000567; //stefan-boltzmann
real Tinf = 298.0; // environment temp
real heff; // effective heat transfer coeff
real Le =6397000 ; //latent heat of evaporation
real M = 0.05893; // molar weight
real C = 8.314; // ideal gas constant
real P ; // saturated vapor pressure


begin_f_loop(f,t)
{
F_CENTROID(x,f,t);
r = x[1];

heff = epsilon*emis*(F_T(f,t)*F_T(f,t)+Tinf*Tinf)*(F_T(f, t)+Tinf);
if ( ( F_T(f,t) >= 1363.0 && F_T(f,t) < 1522.0 ) )

P = 1.013*pow( 10.0, 5.0 )*pow( 10.0 , (-(22209.0/F_T(f,t))-0.000223*F_T(f,t)+7.9366) );

else if ( F_T(f,t) >= 1522.0 && F_T(f,t) < 3200.0 )

P = 0.0050019*pow( 1.0052706 , F_T(f,t) );

else if ( F_T(f,t) >= 3200.0 )

P = 1.013*pow(10.0 , 5.0);

the_current_time = CURRENT_TIME;

if ((the_current_time>=0) && (the_current_time<10))
{
if ( F_T(f,t) < 1363.0 )

flux = abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-r*r/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf);

else if ( F_T(f,t) >= 1363.0 && F_T(f,t) < 1522.0 )

flux = abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-r*r/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf)-Le*M*P/sqrt(2*3.14159*M*C*F_T(f,t));

else if ( F_T(f,t) >= 1522.0 && F_T(f,t) < 3200.0 )

flux = abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-r*r/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf)-Le*M*P/sqrt(2*3.14159*M*C*F_T(f,t));

else if ( F_T(f,t) >= 3200.0 )

flux = abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-r*r/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf)-Le*M*P/sqrt(2*3.14159*M*C*F_T(f,t));
}

else if ((the_current_time>=10.0) && (the_current_time<20.0))
{
if ( F_T(f,t) < 1363.0 )

flux = (abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-((r-0.005)*(r-0.005))/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf));

else if ( F_T(f,t) >= 1363.0 && F_T(f,t) < 1522.0 )

flux = (abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-((r-0.005)*(r-0.005))/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf)-Le*M*P/sqrt(2*3.14159*M*C*F_T(f,t)));

else if ( F_T(f,t) >= 1522.0 && F_T(f,t) < 3200.0 )

flux = (abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-((r-0.005)*(r-0.005))/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf)-Le*M*P/sqrt(2*3.14159*M*C*F_T(f,t)));

else if ( F_T(f,t) >= 3200.0 )

flux = (abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-((r-0.005)*(r-0.005))/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf)-Le*M*P/sqrt(2*3.14159*M*C*F_T(f,t)));
}

else if ((the_current_time>=20) && (the_current_time<30))
{
if ( F_T(f,t) < 1363.0 )

flux = (abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-((r-0.01)*(r-0.01))/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf));

else if ( F_T(f,t) >= 1363.0 && F_T(f,t) < 1522.0 )

flux = (abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-((r-0.01)*(r-0.01))/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf)-Le*M*P/sqrt(2*3.14159*M*C*F_T(f,t)));

else if ( F_T(f,t) >= 1522.0 && F_T(f,t) < 3200.0 )

flux = (abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-((r-0.01)*(r-0.01))/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf)-Le*M*P/sqrt(2*3.14159*M*C*F_T(f,t)));

else if ( F_T(f,t) >= 3200.0 )

flux = (abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-((r-0.01)*(r-0.01))/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf)-Le*M*P/sqrt(2*3.14159*M*C*F_T(f,t)));
}
else if ((the_current_time>=30) && (the_current_time<40))
{

if ( F_T(f,t) < 1363.0 )

flux = (abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-((r-0.015)*(r-0.015))/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf));

else if ( F_T(f,t) >= 1363.0 && F_T(f,t) < 1522.0 )

flux = (abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-((r-0.015)*(r-0.015))/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf)-Le*M*P/sqrt(2*3.14159*M*C*F_T(f,t)));

else if ( F_T(f,t) >= 1522.0 && F_T(f,t) < 3200.0 )

flux = (abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-((r-0.015)*(r-0.015))/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf)-Le*M*P/sqrt(2*3.14159*M*C*F_T(f,t)));

else if ( F_T(f,t) >= 3200.0 )

flux = (abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-((r-0.015)*(r-0.015))/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf)-Le*M*P/sqrt(2*3.14159*M*C*F_T(f,t)));
}
else if ((the_current_time>=40) && (the_current_time<50))
{
if ( F_T(f,t) < 1363.0 )

flux = (abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-((r-0.02)*(r-0.02))/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf));

else if ( F_T(f,t) >= 1363.0 && F_T(f,t) < 1522.0 )

flux = (abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-((r-0.02)*(r-0.02))/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf)-Le*M*P/sqrt(2*3.14159*M*C*F_T(f,t)));

else if ( F_T(f,t) >= 1522.0 && F_T(f,t) < 3200.0 )

flux = (abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-((r-0.02)*(r-0.02))/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf)-Le*M*P/sqrt(2*3.14159*M*C*F_T(f,t)));

else if ( F_T(f,t) >= 3200.0 )

flux = (abs*I*(1.0/(2.0*3.1415926*sigma*sigma))*ti*exp(-((r-0.02)*(r-0.02))/(2*sigma*sigma))-heff*(F_T(f,t)-Tinf)-Le*M*P/sqrt(2*3.14159*M*C*F_T(f,t)));
}


F_PROFILE(f,t,i)=flux;
}
end_f_loop(f,t)
}


DEFINE_INIT(initial,d)
{
cell_t c;
Thread *t;
/* loop over all cell threads in the domain */
thread_loop_c(t,d)
{
/* loop over all cells */
begin_c_loop_all(c,t)
{
C_T(c,t) = 300.0;
}
end_c_loop_all(c,t)
}
}
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