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Title: Comprehensive numerical methodology for direct numerical simulations of compressible Rayleigh-Taylor instability

Abstract

A comprehensive numerical methodology has been developed that handles the challenges introduced by considering the compressive nature of Rayleigh-Taylor instability (RTI) systems, which include sharp interfacial density gradients on strongly stratified background states, acoustic wave generation and removal at computational boundaries, and stratification-dependent vorticity production. The computational framework is used to simulate two-dimensional single-mode RTI to extreme late-times for a wide range of flow compressibility and variable density effects. The results show that flow compressibility acts to reduce the growth of RTI for low Atwood numbers, as predicted from linear stability analysis.

Authors:
 [1];  [2];  [3]
  1. Montana State Univ., Bozeman, MT (United States)
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  3. Univ. of Colorado, Boulder, CO (United States)
Publication Date:
Research Org.:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1321662
Report Number(s):
LA-UR-16-26726
TRN: US1601889
DOE Contract Number:
AC52-06NA25396
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
97 MATHEMATICS AND COMPUTING; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; RAYLEIGH-TAYLOR INSTABILITY; COMPUTERIZED SIMULATION; COMPRESSIBILITY; SOUND WAVES; TWO-DIMENSIONAL CALCULATIONS; INSTABILITY GROWTH RATES; PLASMA DENSITY; STRATIFICATION; VORTICES

Citation Formats

Reckinger, Scott James, Livescu, Daniel, and Vasilyev, Oleg V. Comprehensive numerical methodology for direct numerical simulations of compressible Rayleigh-Taylor instability. United States: N. p., 2016. Web. doi:10.2172/1321662.
Reckinger, Scott James, Livescu, Daniel, & Vasilyev, Oleg V. Comprehensive numerical methodology for direct numerical simulations of compressible Rayleigh-Taylor instability. United States. doi:10.2172/1321662.
Reckinger, Scott James, Livescu, Daniel, and Vasilyev, Oleg V. Fri . "Comprehensive numerical methodology for direct numerical simulations of compressible Rayleigh-Taylor instability". United States. doi:10.2172/1321662. https://www.osti.gov/servlets/purl/1321662.
@article{osti_1321662,
title = {Comprehensive numerical methodology for direct numerical simulations of compressible Rayleigh-Taylor instability},
author = {Reckinger, Scott James and Livescu, Daniel and Vasilyev, Oleg V.},
abstractNote = {A comprehensive numerical methodology has been developed that handles the challenges introduced by considering the compressive nature of Rayleigh-Taylor instability (RTI) systems, which include sharp interfacial density gradients on strongly stratified background states, acoustic wave generation and removal at computational boundaries, and stratification-dependent vorticity production. The computational framework is used to simulate two-dimensional single-mode RTI to extreme late-times for a wide range of flow compressibility and variable density effects. The results show that flow compressibility acts to reduce the growth of RTI for low Atwood numbers, as predicted from linear stability analysis.},
doi = {10.2172/1321662},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Sep 02 00:00:00 EDT 2016},
month = {Fri Sep 02 00:00:00 EDT 2016}
}

Technical Report:

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