Conservative Multimoment Transport along Characteristics for Discontinuous Galerkin Methods

TitleConservative Multimoment Transport along Characteristics for Discontinuous Galerkin Methods
Publication TypeJournal Article
Year of Publication2019
JournalSIAM Journal on Scientific Computing
Volume41
Number4
PagesB870-B902
Date Published08/2019
Abstract / Summary

A set of algorithms based on characteristic discontinuous Galerkin methods is presented for tracer transport on the sphere. The algorithms are designed to reduce MPI communication volume per unit of simulated time relative to current methods generally and to the spectral element scheme employed by the U.S. Dept. of Energy's Exascale Earth System Model (E3SM) model specifically. Two methods are developed to enforce discrete mass conservation when the transport schemes are coupled to a separate dynamics solver, constrained transport and Jacobian-combined transport. A communication-efficient method is introduced to enforce tracer consistency between the transport scheme and dynamics solver; this method also provides the transport scheme's shape preservation capability. A subset of the algorithms derived here is implemented in E3SM and shown to improve transport performance by a factor of 2.2 for the model's standard configuration with 40 tracers at the strong scaling limit of 1 element per core.

URLhttp://dx.doi.org/10.1137/18m1165943
DOI10.1137/18m1165943
Journal: SIAM Journal on Scientific Computing
Year of Publication: 2019
Volume: 41
Number: 4
Pages: B870-B902
Date Published: 08/2019

A set of algorithms based on characteristic discontinuous Galerkin methods is presented for tracer transport on the sphere. The algorithms are designed to reduce MPI communication volume per unit of simulated time relative to current methods generally and to the spectral element scheme employed by the U.S. Dept. of Energy's Exascale Earth System Model (E3SM) model specifically. Two methods are developed to enforce discrete mass conservation when the transport schemes are coupled to a separate dynamics solver, constrained transport and Jacobian-combined transport. A communication-efficient method is introduced to enforce tracer consistency between the transport scheme and dynamics solver; this method also provides the transport scheme's shape preservation capability. A subset of the algorithms derived here is implemented in E3SM and shown to improve transport performance by a factor of 2.2 for the model's standard configuration with 40 tracers at the strong scaling limit of 1 element per core.

DOI: 10.1137/18m1165943
Citation:
Bosler, P, A Bradley, and M Taylor.  2019.  "Conservative Multimoment Transport along Characteristics for Discontinuous Galerkin Methods."  SIAM Journal on Scientific Computing 41(4): B870-B902.  https://doi.org/10.1137/18m1165943.