Reply To: Bounce Back Boundary conditions and lattice nodes locations

[ramirofreile]

Hello Julius,

In page 178 of the Kruger book mentions the following:

Despite what their names might suggest, both the fullway and halfway
approaches assume that the boundary is located approximately midway
between solid and boundary nodes, not on the solid nodes themselves.

Then in page 177 there are two figures that show the difference between half way and fullway bounce back. For the halfway bb, it takes deltat to return to the fluid node at the boundary, and for the fullway it takes 2*deltat. But the wall boundary is at a distance deltax/2 from the closest fluid node to the wall. The Zou He velocity boundary conditions assume that the node is at the wall.

So I still do not know how the AD lattice and NS lattice cope with this.
Thank you,

Ramiro