|March 17, 2016, 07:33||
Problems in converging viscosity UDF dependent upon strain rate and temperature.
Join Date: Mar 2016
Posts: 10Rep Power: 2
I am interpreting a viscosity UDF which is dependent upon temperature and strain rate. The UDF interprets fine but does not lead to convergence and starts diverging from the very start and does not run even a single iteration. My UDF is as follows:
double stress = 22.22e+06;
double A = 8.86e+06;
double energy = 145000;
double R = 8.314;
double n = 3.55;
A similar viscosity model named carreau dependent upon strainrate and temperature converges fine but my udf does not even start iterating. It gives the error message
#Divergence detected in AM solver: x-momentum - Increasing relaxation sweeps!
Kindly help me in this my complete project depends upon the successful implementation of the viscosity UDF.
|March 17, 2016, 08:19||
Join Date: Nov 2013
Posts: 895Rep Power: 12
Print the values to your screen.
Message("Z,D,E,F: %f,%f,%f,%f\n",Z,D,E,F); Message("Mu: %f\n",mu_laminar); return mu_laminar;
Then check if the values that are shown agree to what you want. If they don't, find out why not and fix your equations.
|fluent - udf, udf and programming, udf compile, udf eror|
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