[cfx_newbie]

Hey guys,

I got a Problem while modeling porous media in ANSYS CFX.
I want to depict a heatsink regarding dP (total pressure) and the temperature difference.

At first i started a measurement series on the heatsink with different flow rates. From this series i got the parameter for my porous domain (quadratic and linear coefficient, quadratic interpolation of experimental dP overvariable flow rates --> Ansys Guide).

Then I calculated the (fluid-)porosity of my heatsink (Ainlet_fluid /Ainlet_(solid+fluid)) which is equal to V_fluid/V_(fluid+solid) and the IAD. I got the heat transfer coefficient from my comparative measurement.

After that I parameterized the porous domain (Fluid and Solid Model, directional loss Definition, true velocity, streamwise and transverse loss [lin and quadr. resistance coeff], IAD and htc)

When my run finished i got a completely different solution to my reference calculation.

dP (porous Media) = 2* dP (reference)
P_max (porous Media) = 2* P_max (reference)
P_min (porous Media) = 2* P_min (reference)

Just my average velocity is equal to my reference value (0% difference)...

I wondered about the relation between my result from the run with porous media and the reference run. The total pressure (p_max, p_min and dP) is around the factor 2 bigger than in my Reference simulation.

Maybe someone could help me with this. I miss the forest for the trees