Title: Direct simulation Monte Carlo on petaflop supercomputers and beyond

Abstract

The gold-standard definition of the Direct Simulation Monte Carlo (DSMC) method is given in the 1994 book by Bird [Molecular Gas Dynamics and the Direct Simulation of Gas Flows (Clarendon Press, Oxford, UK, 1994)], which refined his pioneering earlier papers in which he first formulated the method. In the intervening 25 years, DSMC has become the method of choice for modeling rarefied gas dynamics in a variety of scenarios. The chief concern to applying DSMC to more dense or even continuum flows is its computational expense compared to continuum computational fluid dynamics methods. The dramatic (nearly billion-fold) increase in speed of the largest supercomputers over the last 30 years has thus been a key enabling factor in using DSMC to model a richer variety of flows, due to the method’s inherent parallelism. We have developed the open-source SPARTA DSMC code with the goal of running DSMC efficiently on the largest machines, both current and future. It is largely an implementation of Bird’s 1994 formulation. In this work, we describe algorithms used in SPARTA to enable DSMC to operate in parallel at the scale of many billions of particles or grid cells, or with billions of surface elements. We highlight amore » few examples of the kinds of fundamental physics questions and engineering applications that DSMC can address at these scales.« less

Authors:

Plimpton, S. J. ^[1]; Moore, S. G. ^[1]; Borner, A. ^[2]; Stagg, A. K.  ^[1];

• Search DOE PAGES for author "Stagg, A. K."
• Search DOE PAGES for ORCID "0000-0002-0155-7025"

Koehler, T. P. ^[1]; Torczynski, J. R.  ^[1];

• Search DOE PAGES for author "Torczynski, J. R."
• Search DOE PAGES for ORCID "0000-0002-6469-895X"

Gallis, M. A.  ^[1]

• Search DOE PAGES for author "Gallis, M. A."
• Search DOE PAGES for ORCID "0000-0002-4985-6956"

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+ Show Author Affiliations

1. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2. Science and Technology Corporation at NASA Ames Research Center, Moffett Field, California 94035, USA

Publication Date:

Thu Aug 01 00:00:00 EDT 2019

Research Org.:

Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

Sponsoring Org.:

USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:

1559524

Report Number(s):

SAND-2019-9819J
Journal ID: ISSN 1070-6631; 678677; TRN: US2000361

Grant/Contract Number:  

AC04-94AL85000; NA0003525

Resource Type:

Accepted Manuscript

Journal Name:

Physics of Fluids

Additional Journal Information:

Journal Volume: 31; Journal Issue: 8; Journal ID: ISSN 1070-6631

Publisher:

American Institute of Physics (AIP)

Country of Publication:

United States

Language:

English

Subject:

97 MATHEMATICS AND COMPUTING; Direct Simulation Monte Carlo; DSMC; parallel algorithms; SPARTA