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LBM, 2D Poiseuille flowHi
I am trying to implement the 2D Poiseuille flow with the Lattice Boltzmann method, and I am using "on-grid bounce back" boundary conditions. I have implemented it, but my velocity-profile is strange. There is a finite velocity at the boundary, but I was under the impression that the whole point of the bounce-back BC was to ensure no-slip. My velocity profile looks like this. Does this behavior at the boundary imply an error in my implementation? I'd be happy to post my code, if anyone is interested in taking a look. Thanks in advance, Niles. |

It's been quite a while since I implemented LBM for channel flow.
But it should be correct, that you get a finite velocity at the walls. The magnitude of this velocity depends on your lattice size. If you decrease the mesh size, the velocity at the walls should tend to zero. |

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