[pertupd]

Hy all,
I trying to set porous jump model in fluent to model 3D flow over perforated plate (cca, 10 mm in thickness).
I computed inertial resistance and face permeability according to fluent 6.3 User guide 7.19.6 paragraph based on tabulated values of delta pressure - velocity (dp-c) dependence. The dp-c was determined based on detail fluid flow over element of the perforated plate.
I approximated dp-c dependence by quadratic equation:
dp=a*c^2 + b*c
But the b coefficient is negative for my case and thus the permeability value (alfa) too.
Problem is that fluent does not accept negative value of alfa.
How to input the alfa?
if I thing that the model with dp=.. -b*c is different to the dp=.. +b*c.

By the way the value of alfa is rather small (of order of 1.e-7) - thus enhancing einfluence of inertial resistance.
Order of C2 (inertial resistance coefficient) is cca 500 for the plate.

Thanks.

[will321321]

Hello,

I am Having the same problem with the same procedure can someone please enlighten us.

thank you.