skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Extended model for Richtmyer-Meshkov mix

Abstract

We examine four Richtmyer-Meshkov (RM) experiments on shock-generated turbulent mix and find them to be in good agreement with our earlier simple model in which the growth rate h of the mixing layer following a shock or reshock is constant and given by 2{alpha}A{Delta}v, independent of initial conditions h{sub 0}. Here A is the Atwood number ({rho}{sub B}-{rho}{sub A})/({rho}{sub B} + {rho}{sub A}), {rho}{sub A,B} are the densities of the two fluids, {Delta}V is the jump in velocity induced by the shock or reshock, and {alpha} is the constant measured in Rayleigh-Taylor (RT) experiments: {alpha}{sup bubble} {approx} 0.05-0.07, {alpha}{sup spike} {approx} (1.8-2.5){alpha}{sup bubble} for A {approx} 0.7-1.0. In the extended model the growth rate beings to day after a time t*, when h = h*, slowing down from h = h{sub 0} + 2{alpha}A{Delta}vt to h {approx} t{sup {theta}} behavior, with {theta}{sup bubble} {approx} 0.25 and {theta}{sup spike} {approx} 0.36 for A {approx} 0.7. They ascribe this change-over to loss of memory of the direction of the shock or reshock, signaling transition from highly directional to isotropic turbulence. In the simplest extension of the model h*/h{sub 0} is independent of {Delta}v and depends only on A. They find that h*/h{submore » 0} {approx} 2.5-3.5 for A {approx} 0.7-1.0.« less

Authors:
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1020330
Report Number(s):
LLNL-JRNL-420428
TRN: US201116%%263
DOE Contract Number:  
W-7405-ENG-48
Resource Type:
Journal Article
Journal Name:
Physica D , vol. 240, no. 11, February 24, 2011, pp. 935-942
Additional Journal Information:
Journal Volume: 240; Journal Issue: 11
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUMM MECHANICS, GENERAL PHYSICS; SLOWING-DOWN; TURBULENCE; VELOCITY

Citation Formats

Mikaelian, K O. Extended model for Richtmyer-Meshkov mix. United States: N. p., 2009. Web.
Mikaelian, K O. Extended model for Richtmyer-Meshkov mix. United States.
Mikaelian, K O. 2009. "Extended model for Richtmyer-Meshkov mix". United States. https://www.osti.gov/servlets/purl/1020330.
@article{osti_1020330,
title = {Extended model for Richtmyer-Meshkov mix},
author = {Mikaelian, K O},
abstractNote = {We examine four Richtmyer-Meshkov (RM) experiments on shock-generated turbulent mix and find them to be in good agreement with our earlier simple model in which the growth rate h of the mixing layer following a shock or reshock is constant and given by 2{alpha}A{Delta}v, independent of initial conditions h{sub 0}. Here A is the Atwood number ({rho}{sub B}-{rho}{sub A})/({rho}{sub B} + {rho}{sub A}), {rho}{sub A,B} are the densities of the two fluids, {Delta}V is the jump in velocity induced by the shock or reshock, and {alpha} is the constant measured in Rayleigh-Taylor (RT) experiments: {alpha}{sup bubble} {approx} 0.05-0.07, {alpha}{sup spike} {approx} (1.8-2.5){alpha}{sup bubble} for A {approx} 0.7-1.0. In the extended model the growth rate beings to day after a time t*, when h = h*, slowing down from h = h{sub 0} + 2{alpha}A{Delta}vt to h {approx} t{sup {theta}} behavior, with {theta}{sup bubble} {approx} 0.25 and {theta}{sup spike} {approx} 0.36 for A {approx} 0.7. They ascribe this change-over to loss of memory of the direction of the shock or reshock, signaling transition from highly directional to isotropic turbulence. In the simplest extension of the model h*/h{sub 0} is independent of {Delta}v and depends only on A. They find that h*/h{sub 0} {approx} 2.5-3.5 for A {approx} 0.7-1.0.},
doi = {},
url = {https://www.osti.gov/biblio/1020330}, journal = {Physica D , vol. 240, no. 11, February 24, 2011, pp. 935-942},
number = 11,
volume = 240,
place = {United States},
year = {Wed Nov 18 00:00:00 EST 2009},
month = {Wed Nov 18 00:00:00 EST 2009}
}