# Computational Mathematics and Scientific Computing Seminar

## Algorithms for Generating Initial Guesses for Sequences of Linear Systems in a GPU-Accelerated Incompressible Flow Solver

**Speaker:**
Tim Warburton, Virginia Polytechnic Institute and State University

**Location:**
Warren Weaver Hall (online)

**Date:**
Nov. 6, 2020, 10 a.m.

**Synopsis:**

I will discuss some of the challenges of scaling up flow simulations to the next generation of US Department of Energy leadership computing facilities as we enter the exascale computing era. I will illustrate some trade-offs we make when balancing computational and algorithmic efficiency by comparing different algorithms used to generate initial guesses when solving a sequence of linear systems resulting from time-stepping the time dependent incompressible Navier-Stokes equations with high-order finite element spatial discretizations. I will also introduce the libParanumal software library for GPU accelerated finite element analysis and discuss how it has been used by the NekRS thermofluids solver to run on the whole Summit leadership computing facility at Oakridge National Laboratory at high parallel efficiency.

This work was sponsored in part by the Department of Energy Exascale Computing Project through a subcontract to the Center for Efficient Exascale Discretizations, Lawrence Livermore National Laboratory.

See https://cs.nyu.edu/dynamic/news/seminars/1/ for how to join the seminar via Zoom