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UDF for modified drag force

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Old   May 12, 2015, 08:59
Default UDF for modified drag force
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Burak EKMEKÇİ
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Hi all;

I am trying to obtain a udf that consist of real Turbulence variable (TKE or Turbulence intensity or etc). Main aim is to change Drag Force. A sample is below ;

#include "udf.h"

DEFINE_DPM_DRAG(particle_drag_force,Re,p)
{
real w, drag_force;
if (Re < 0.01)
{
drag_force=18.0;
return (drag_force);
}
else if (Re < 20.0)
{
w = log10(Re);
drag_force = 18.0 + 2.367*pow(Re,0.82-0.05*w) ;
return (drag_force);
}
else
/* Note: suggested valid range 20 < Re < 260 */
{
drag_force = 18.0 + 3.483*pow(Re,0.6305) ;
return (drag_force);
}
}

Is it possible to add real TKE value into to UDF ? or how can ı do ? For example when ı change codes like ;

else if (Re < 20.0)
{
w = log10(TKE);
drag_force = 18.0 + 2.367*pow(Re,0.82-0.05*w) ;
return (drag_force);

It does not work.

Thanks for your helps.

Best regards!
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Old   May 17, 2015, 09:16
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Burak EKMEKÇİ
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Any commend ?
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