OpenLB – Open Source Lattice Boltzmann Code › Forums › on Lattice Boltzmann Methods › General Topics › addSlipBoundary › Re: addSlipBoundary March 28, 2018 at 8:00 am #2821 mario.ponceMember Hi Mathias, Indeed It is irregular. However, I’m trying to add it to the top of the geometry that is parallel to the plane z.