Off lattice boundary conditions

Hello,

I have been reading a few papers recently about off lattice boundary conditions (eg X. He et al 2009, computers & fluids; Chang et al 2009, computers & mathematics with applications). Does anyone have any ideas about whether or not the Palabos collision operator for bounce back nodes could be modified for off lattice boundary conditions?

I was thinking that it might work if the collision process could read from a tensor field containing the distances between the fluid cells and the boundary in each direction which I might be able to get either from an analytical description of the geometry or some smoothing algorithm. Does this sound reasonable?

If anyone has any experience in this area or ideas I’d like to hear them. Thanks in advance for any help.

Alex White

Hi Alex,

It sounds reasonable. In the future I planned to do it with my in-house code but don’t know whether Palabos have it. You need to address so-called link bounce-back (you can read from H. Kusumaatmaja thesis - just google it) and access the information through the tensor field.

Alex

Thanks Alex, the thesis explains it really clearly. I’ll let you know how I get on when I finally get round to trying this.

Alex