Dear Earl and Wolfgang, Thanks for the very thorough answer. I will definitely look into it this year and try to come up with a solution. I think there are many ways to tackle this type of approach using the existing tools :) I'll keep you informed should I find a way to make a decent implementation. Best! Bruno
On Sunday, 16 June 2019 21:13:32 UTC-4, Wolfgang Bangerth wrote: > > > Bruno, > > > As some of you might know, sliding mesh approaches are generally used in > CFD > > simulation of rotating geometries without axial symmetry (for instance, > an > > impeller with baffles). > > This is generally achieved by having two triangulation, one that is > rotating > > and one that is static. At the interface between the meshes, constraints > are > > used to "bridge" the two meshes together. Although this generally > induces > > additional interpolation error, this is generally one of the best way to > deal > > with turbomachinery. > > > > Since dealii is already equipped to deal with contact problem, has > anybody > > ever investigated if a sliding-mesh type of simulation could be carried > out > > using dealii? > > I don't know, but then there are 1,200+ publications at > https://dealii.org/publications.html > that might contain something you're looking for. There's now even a search > function :-) > > There are going to be two challenges: > * Mesh generation. Earl Fairall already commented on that. > * Generation of the constraints. That's going to be difficult because > you'll have to find quadrature points on the faces of one mesh on the > faces of the other mesh, and these sorts of point search algorithms > are always expensive (though easy to parallelize). You need this kind > of mapping if you want to project between the two mesh surfaces; for > interpolation, you'll need to find the location of the support points > of the faces of one mesh on the faces of the other mesh, which is the > same kind of operation. > > You could consider a mortar approach in which you would have a third mesh > at > the interface. In that case, you could choose at least one of the meshes > involved to be somewhat structured, but in the end, it's probably going to > be > about as expensive as otherwise. > > I don't know anyone who has implemented the exact kind of application you > have, but you might want to look up some of the work done on > fluid-structure > interaction in deal.II (e.g., by Thomas Wick). I *believe* that they too > have > to interpolate between different kinds of meshes. There is also the > 'nonmatching' namespace that was added by Luca Heltai and coworkers in the > last release that helps you deal with overlay meshes -- which would also > be a > way to do what you're looking at -- the rotating geometry would simply be > an > overlay to a background mesh. I believe there is also a tutorial program > for that. > > Other than that, I have no real pointers. But it's an interesting topic, > and > if you find ways to implement what you are looking for, please feel free > to > post solutions here (and/or make small test programs available as code > gallery > or tutorial program! > > Best > W. > > > -- > ------------------------------------------------------------------------ > Wolfgang Bangerth email: [email protected] > <javascript:> > www: http://www.math.colostate.edu/~bangerth/ > > -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/3fdbf6a1-cd04-4e0d-82bd-859a032091e3%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
