[aulu]

Hello everybody,

I'm modelling a gas flow where a porous particle is inside. The porosity changes with increasing temperature by an udf. So I want to change the viscous and inertial resistance with changing temperature too. But there than FLUENT tells me, that there is a divergence detected in momentum.
The viscous resistance is calculated like this: 150 * (1 - porosity)^2/ (D_p^2 * porosity^3);

The viscous resistance is calculated like this: 3.5 * (1 - porosity) /(porosity^3*D_p);

Thanks in advance.