[kalyan]

Hello everyone,

i want to simulate flow over perforated plate which is inside a cylinder. using topoSet i have created a cellSet for perforated plate. Now how can i define this cellSet as wall? the perforated plate is 2mm thick. i tried using createBaffles but there was some error from solver.. any help is greatly appreciated. Thankyou

[alexeym]

Hi,

As it is just "flow" I assume that it is incompressible flow and you are using pimpleFoam solver. You can use explicitPorositySource fvOption with very high Darcy (d) coefficient (you can set Forchheimer coefficient to 0) for your cellSet.

[kalyan]

Hi,

Thank you for the reply. I think the solution you said should work.

Regards,
Kalyan

[kalyan]

Hi alexey,

I have few doubts. what happens if i give some value to f (forchheimer coefficient) for explicit porosity?

As mentioned in the first post, i have created a 2mm thickness Plate with holes(perforated plate) as cellZone. Now i used this cellZone as porous medium and defined values as d = 0 and f = 10^7. The results looks fine, like velocity of the air at the cellZone is 0 and flow is only though non cellZone(i.e holes).

my doubt is that is how to select the values of d and f(darcy and forchheimer coefficient for explicit porosity) such that the porous medium almost behaves like wall.

** a little correction, flow is not incompressible. i am using air as fluid, and solver is rhoPimpleFoam

Thank you

Regards,
kalyan

[alexeym]

Hi,

Well, it will be easier to go with d ~ 1e16 and f ~ 0. To estimate d you can use, for example, Kozeny-Carman (https://en.wikipedia.org/wiki/Kozeny–Carman_equation) equation. In your case as you would like medium to act like a solid, epsilon in the equation should be low.