Latetime growth rate, mixing, and anisotropy in the multimode narrowband Richtmyer–Meshkov instability: The θgroup collaboration
Turbulent Richtmyer–Meshkov instability (RMI) is investigated through a series of high resolution threedimensional simulations of two initial conditions with eight independent codes. The simulations are initialised with a narrowband perturbation such that instability growth is due to nonlinear coupling/backscatter from the energetic modes, thus generating the lowest expected growth rate from a pure RMI. By independently assessing the results from each algorithm and computing ensemble averages of multiple algorithms, the results allow a quantification of key flow properties as well as the uncertainty due to differing numerical approaches. A new analytical model predicting the initial layer growth for a multimode narrowband perturbation is presented, along with two models for the linear and nonlinear regimes combined. Overall, the growth rate exponent is determined as θ=0.292±0.009, in good agreement with prior studies; however, the exponent is decaying slowly in time. Also, θ is shown to be relatively insensitive to the choice of mixing layer width measurements. The asymptotic integral molecular mixing measures Θ=0.792±0.014, Ξ=0.800±0.014, and Ψ=0.782±0.013 are lower than some experimental measurements but within the range of prior numerical studies. The flow field is shown to be persistently anisotropic for all algorithms, at the latest time having between 49% and 66% highermore »
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 Univ. of Sydney, NSW (Australia). School of Aerospace, Mechanical and Mechatronic Engineering
 Alternative Energies and Atomic Energy Commission (CEA), Arpajon (France)
 Univ. of North Carolina, Charlotte, NC (United States). Mechanical Engineering and Engineering Science
 Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
 AWE, Aldermaston (United Kingdom)
 Russian Academy of Sciences (RAS), Moscow (Russian Federation). Keldysh Inst. of Applied Mathematics; Russian Academy of Sciences (RAS), Moscow (Russian Federation). P.N. Lebedev Physical Inst.
 Russian Academy of Sciences (RAS), Moscow (Russian Federation). Keldysh Inst. of Applied Mathematics
 Russian Academy of Sciences (RAS), Moscow (Russian Federation). P.N. Lebedev Physical Inst.
 Univ. of Strathclyde, Glasgow (Scotland). Dept. of Mechanical and Aerospace Engineering
 Publication Date:
 Report Number(s):
 LLNLJRNL733858
Journal ID: ISSN 10706631; 885603
 Grant/Contract Number:
 AC5207NA27344; AC5207NA2734; AC5206NA25396
 Type:
 Accepted Manuscript
 Journal Name:
 Physics of Fluids
 Additional Journal Information:
 Journal Volume: 29; Journal Issue: 10; Journal ID: ISSN 10706631
 Publisher:
 American Institute of Physics (AIP)
 Research Org:
 Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
 Sponsoring Org:
 USDOE National Nuclear Security Administration (NNSA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS
 OSTI Identifier:
 1468910
 Alternate Identifier(s):
 OSTI ID: 1402116
Thornber, B., Griffond, J., Poujade, O., Attal, N., Varshochi, H., Bigdelou, P., Ramaprabhu, P., Olson, B., Greenough, J., Zhou, Y., Schilling, O., Garside, K. A., Williams, R. J. R., Batha, C. A., Kuchugov, P. A., Ladonkina, M. E., Tishkin, V. F., Zmitrenko, N. V., Rozanov, V. B., and Youngs, D. L.. Latetime growth rate, mixing, and anisotropy in the multimode narrowband Richtmyer–Meshkov instability: The θgroup collaboration. United States: N. p.,
Web. doi:10.1063/1.4993464.
Thornber, B., Griffond, J., Poujade, O., Attal, N., Varshochi, H., Bigdelou, P., Ramaprabhu, P., Olson, B., Greenough, J., Zhou, Y., Schilling, O., Garside, K. A., Williams, R. J. R., Batha, C. A., Kuchugov, P. A., Ladonkina, M. E., Tishkin, V. F., Zmitrenko, N. V., Rozanov, V. B., & Youngs, D. L.. Latetime growth rate, mixing, and anisotropy in the multimode narrowband Richtmyer–Meshkov instability: The θgroup collaboration. United States. doi:10.1063/1.4993464.
Thornber, B., Griffond, J., Poujade, O., Attal, N., Varshochi, H., Bigdelou, P., Ramaprabhu, P., Olson, B., Greenough, J., Zhou, Y., Schilling, O., Garside, K. A., Williams, R. J. R., Batha, C. A., Kuchugov, P. A., Ladonkina, M. E., Tishkin, V. F., Zmitrenko, N. V., Rozanov, V. B., and Youngs, D. L.. 2017.
"Latetime growth rate, mixing, and anisotropy in the multimode narrowband Richtmyer–Meshkov instability: The θgroup collaboration". United States.
doi:10.1063/1.4993464. https://www.osti.gov/servlets/purl/1468910.
@article{osti_1468910,
title = {Latetime growth rate, mixing, and anisotropy in the multimode narrowband Richtmyer–Meshkov instability: The θgroup collaboration},
author = {Thornber, B. and Griffond, J. and Poujade, O. and Attal, N. and Varshochi, H. and Bigdelou, P. and Ramaprabhu, P. and Olson, B. and Greenough, J. and Zhou, Y. and Schilling, O. and Garside, K. A. and Williams, R. J. R. and Batha, C. A. and Kuchugov, P. A. and Ladonkina, M. E. and Tishkin, V. F. and Zmitrenko, N. V. and Rozanov, V. B. and Youngs, D. L.},
abstractNote = {Turbulent Richtmyer–Meshkov instability (RMI) is investigated through a series of high resolution threedimensional simulations of two initial conditions with eight independent codes. The simulations are initialised with a narrowband perturbation such that instability growth is due to nonlinear coupling/backscatter from the energetic modes, thus generating the lowest expected growth rate from a pure RMI. By independently assessing the results from each algorithm and computing ensemble averages of multiple algorithms, the results allow a quantification of key flow properties as well as the uncertainty due to differing numerical approaches. A new analytical model predicting the initial layer growth for a multimode narrowband perturbation is presented, along with two models for the linear and nonlinear regimes combined. Overall, the growth rate exponent is determined as θ=0.292±0.009, in good agreement with prior studies; however, the exponent is decaying slowly in time. Also, θ is shown to be relatively insensitive to the choice of mixing layer width measurements. The asymptotic integral molecular mixing measures Θ=0.792±0.014, Ξ=0.800±0.014, and Ψ=0.782±0.013 are lower than some experimental measurements but within the range of prior numerical studies. The flow field is shown to be persistently anisotropic for all algorithms, at the latest time having between 49% and 66% higher kinetic energy in the shock parallel direction compared to perpendicular and does not show any return to isotropy. The plane averaged volume fraction profiles at different time instants collapse reasonably well when scaled by the integral width, implying that the layer can be described by a single length scale and thus a single θ. In conclusion, quantitative data given for both ensemble averages and individual algorithms provide useful benchmark results for future research.},
doi = {10.1063/1.4993464},
journal = {Physics of Fluids},
number = 10,
volume = 29,
place = {United States},
year = {2017},
month = {10}
}