3D Grid Refinement

Dear community,

I’m currently trying non-nested 3D grid refinement. In my case each lattice level reaches the side boundaries of the domain which are periodical in z direction. In order to conserve cubic cuboids, the domain is created with removeBlocks=true. Everything works fine inside the domain but on the side boundaries at each grid level interface there are singularities (fluid speed moving up close to zero). Is there a way of getting rid of those singularities?

Thank you,