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Divergence in non-Newtonian fluid UDF

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Old   June 23, 2016, 11:30
Default Divergence in non-Newtonian fluid UDF
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mohsen
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Hi
I have written an UDF for a non-Newtonian fluid. first, i run the project with steady and constant viscosity for 10 iteration and after that i hooked the UDF but i faced with this divergence error:
# Divergence detected in AMG solver: epsilon -> Increasing relaxation sweeps!
# You may try the enhanced divergence recovery with (rpsetvar 'amg/protective-enhanced? #t)

turbulent viscosity limited to viscosity ratio of 1.000000e+20 in 249582 cells

reversed flow in 1614 faces on pressure-outlet 13.

Divergence detected in AMG solver: epsilon
Divergence detected in AMG solver: epsilon
Divergence detected in AMG solver: epsilon
Divergence detected in AMG solver: epsilon
Divergence detected in AMG solver: epsilon
Error at host: floating point exception

Error at Node 0: floating point exception

Error at Node 1: floating point exception

Error at Node 2: floating point exception

Error at Node 3: floating point exception

Error at Node 4: floating point exception

Error: floating point exception
Error Object: #f


UDF is:

#include "udf.h"


DEFINE_PROPERTY(cell_viscosity,c,t)
{
#if !RP_NODE
real SR=C_STRAIN_RATE_MAG(c,t);
real n=0.70;
real k=0.00103;
real PV=0.0001;
real YP=2.8728;
real YSR=0.018;
real EV;
real SS;

SS=k*exp(n*log(SR));
EV=(SS/SR)+k*(exp((1-n)*log(SR/YSR)));

return EV;
#endif
}


now, what should i do for fix that ERROR.
it's my pleasure if somebody could help me.

thanks
BEST REGARDS
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