On Wed, May 11, 2011 at 04:20, Sylvain Barbot <sylbar.vainbot at gmail.com>wrote:
> I am still trying to design a > multigrid preconditionner for the Navier's equation of elasticity. > I have heard, through an external source, that you have large jumps in both Young's modulus and Poisson ratio that are not grid aligned, including perhaps thin structures that span a large part of the domain. Such problems are pretty hard, so I suggest you focus on robustness and do not worry about low-memory implementation at this point. That is, you should assemble the matrices in a usual PETSc format instead of using MatShell to do everything matrix-free. This gives you access to much stronger smoothers. After you find a scheme that is robust enough for your purposes, _then_ you can make it low-memory by replacing some assembled matrices by MatShell. To realize most of the possible memory savings, it should be sufficient to do this on the finest level only. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20110511/998e273a/attachment.htm>
