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Help!UDF viscosity

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Old   May 5, 2014, 08:46
Default Help!UDF viscosity
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Weiliang Hou
Join Date: May 2014
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I write a UDF viscosity code.I want to define a kind of non-newtonian fuild in laminar flow, and its viscosity is changed with time. But the viscosity is homegeneous in stirring and not shear thinning.The code is here.So I want to how I can modify this code. Thank you very much!

#include "udf.h"
DEFINE_PROPERTY(cell_viscosity,c,t)
{
real time,vis, s_mag,n,kp;
time = RP_Get_Real("flow-time");
s_mag=C_STRAIN_RATE_MAG(c,t);
if(time<32400)
{
kp=0.095552*pow(time/3600,4)-2.5696*pow(time/3600,3)+25.13*pow(time/3600,2)-107.13*time/3600+179;
n=0.000075452*pow(time/3600,6)-0.0020979*pow(time/3600,5)+0.022364*pow(time/3600,4)-0.11435*pow(time/3600,3)+0.28236*pow(time/3600,2)-0.23947*time/3600+0.214;
}
else
{
kp=3.82832;
n=0.518373;
}
s_mag=38.211*pow(1.11,2/n)*pow(n*(pow(1.11,2/n-1)-1)/(2-n)/0.11,1/(n-1))/(pow(1.21,2/n)-1)/n;
vis=kp*pow(s_mag,(n-1));
return vis;
}
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