Berkeley Lab - Scientific Computing Seminar

Date:

Tuesday, April 29, 2008

Time:

1:00pm-2:00pm

Location:

Building 50B, 4205 Conference Room

Seminar Speaker:

Chun Sun
Rensselaer Polytechnic Institute

Title:

Parallel Algebraic Multigrid for Incompressible Finite Element Navier Stokes Solver

Abstract:

We present a parallel Algebraic Multigrid (AMG) algorithm that works with a Parallel Navier-Stokes Finite Element solver PHASTA. It is used as a preconditioner for a Conjugate Gradient (CG) solver that solves the Pressure Poisson Equation. The algorithm consists of a scalable multilevel AMG and a Generalized Global Basis (GGB) accelerator which is also parallel. Significant challenges also included maintaining the algorithms performance using on-part-assembled (globally incomplete on partition boundaries) matrices. We observed a dramatic reduction in CG iteration vectors used per solve for various problems whose sizes vary from 0.1M to 20M. The algorithm is scalable since the number of iteration vectors remains at the same level as the number of processors used increases from 1 (serial) to 16K on IBM BlueGene/L.

Sponsor of Seminar:

Esmond G. Ng

Scientific Computing

Contact Esmond G. Ng EGNg@lbl.gov