Re: [ESPResSo-users] Lattice Boltzmann Boundaries

[Georg Rempfer]

We have used that in the past. Seems to work fine. Make sure to leave enough space between sphere and velocity boundaries, so they don't influence your results.

On Thu, Jul 4, 2019 at 4:48 PM Kai Szuttor <address@hidden> wrote:

Hi,

you can try to use LB boundaries with velocity boundary conditions but I have not tested this myself.

Best,

Kai

> Am 04.07.2019 um 16:02 schrieb Martin Kaiser <address@hidden>:
>
> Hi everybody,
>
> I have a question regarding the box boundaries in a Lattice Boltzmann Simulation. The situation is as follows:
>
> I took the code from the LBM  Tutorial Part 1, where there is a square tube with a sphere in the centre. The flow is created just as in the sample code. My problem is that, for what I need to do, I need to change the parameters so that I see vortices behind the sphere (increasing Reynolds number). Due to the periodic boundary conditions on the open ends of the tube, the “tail” that is created behind the sphere re-enters the simulation box from the other side and thus perturbing my system in an unwanted way.
>
> Is there a smart way in ESPRESSO to bypass this, creating an ,sort of, inlet and outflow boundary conditions on the open ends of the tube?
>
> I hope that my issue is clear, all the best,
> Martin