[BANANA] Berkeley Lab - Scientific Computing Seminar, April 29, 2008

[Esmond G. Ng]

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.