On Architecture and Performance of Adaptive Mesh Refinement in an Electrostatics Particle-In-Cell Code

TL;DR

This paper introduces a hardware-independent adaptive mesh refinement Poisson solver integrated into the OPAL code, enabling scalable large-scale beam simulations in high intensity cyclotrons.

Contribution

It presents a novel, portable adaptive mesh refinement implementation based on Trilinos and AMReX, tailored for electrostatic Particle-In-Cell simulations.

Findings

Validated with analytical solutions and multigrid solver comparisons

Demonstrated parallel scalability on large-scale problems

Enabled precise neighboring bunch simulations in high intensity cyclotrons

Abstract

This article presents a hardware architecture independent implementation of an adaptive mesh refinement Poisson solver that is integrated into the electrostatic Particle-In-Cell beam dynamics code OPAL. The Poisson solver is solely based on second generation Trilinos packages to ensure the desired hardware portability. Based on the massively parallel framework AMReX, formerly known as BoxLib, the new adaptive mesh refinement interface provides several refinement policies in order to enable precise large-scale neighbouring bunch simulations in high intensity cyclotrons. The solver is validated with a built-in multigrid solver of AMReX and a test problem with analytical solution. The parallel scalability is presented as well as an example of a neighbouring bunch simulation that covers the scale of the later anticipated physics simulation.