[gaza]

Hi All,
I want to write a BC where in each iteration gradient of U is calculated and applied on the wall. From which type of BC should I start?

[hanness]

Hy Przemek,

can't you just use "timeVaringMappedFixedValue"-BC? See for example the pitzDailyExptInlet-tutorial.

Regards
Hannes

[gaza]

Hi Hannes,
Thank you very much for your respond.

timeVaringMappedFixedValue BC seems to be to complicated for me.
I am wondering if I can start from fixedValue BC which is basic one.
In my casy in each iteration I only need to calculate gradient of velocity and apply it on a wall. Do you think that this BC is appropriate?

[hanness]

Hi Przemek,

maybe I don't quite get your intention. How do you want to calculate the gradient? Are you doing that with some other parameters? Then I would try to take one of the BCs from the src/finiteVolume/fields/fvPatchFields/derived/ folder and delete what you don't need (e.g. fixedShearStress). For me it is easier to adapt them instead of the higher level BCs.

Regards
Hannes

[gaza]

Hi Hannes,
Basically, I have Ubis variable which is a function of some parameters. Ubis is a volVectorField and I calculate it in each iteration. I have to assign to the wall Ubis component which is parallel to the wall. So I have to assign a nonuniform field on the walls and I do not know which type of BC is good for a starting point.