For more information about this meeting, contact Hope Shaffer, Chun Liu.
|Title:||Block Preconditioning for Multi-physics: From Jacobi to Schur Complements|
|Seminar:||CCMA Luncheon Seminar|
|Speaker:||Eric Cyr, Sandia National Laboratory (Host: J Xu)|
|Developing scalable solvers for fully-coupled multi-physics is challenging. One approach is to use advanced multigrid algorithms to achieve scalability on these problems. However, this approach can suffer from stability issues, in particular the coarse grid operators used in AMG can become ill-conditioned. An alternative to fully-coupled multigrid is to use a block decomposition of the linear system. This segregates the linear system into physical fields. For instance separating Navier-Stokes into velocity and pressure components leads to a 2x2 Jacobian operator. These approaches are appealing because segregated operators are more amenable to multigrid, yet achieving good parallel scalability for the coupled system is still possible. The difficulty with these methods is efficiently and effectively handling the coupling between the different physics. In this talk I will overview a number of block preconditioners focusing on exploiting the structure of the operators. Furthermore, I will present a few techniques for approximating Schur-complement operators. To make this concrete, applications in fluid dynamics and magnetohydrodynamics will be discussed.|
Room Reservation Information
|Date:||11 / 10 / 2014|
|Time:||12:20pm - 01:30pm|