Formation of largescale structures with sharp density gradient through RayleighTaylor growth in a twodimensional slab under the twofluid and finite Larmor radius effects
Abstract
Twofluid and the finite Larmor effects on linear and nonlinear growth of the RayleighTaylor instability in a twodimensional slab are studied numerically with special attention to highwavenumber dynamics and nonlinear structure formation at a low βvalue. The two effects stabilize the unstable high wave number modes for a certain range of the βvalue. In nonlinear simulations, the absence of the high wave number modes in the linear stage leads to the formation of the density field structure much larger than that in the singlefluid magnetohydrodynamic simulation, together with a sharp density gradient as well as a large velocity difference. The formation of the sharp velocity difference leads to a subsequent KelvinHelmholtztype instability only when both the twofluid and finite Larmor radius terms are incorporated, whereas it is not observed otherwise. It is shown that the emergence of the secondary instability can modify the outline of the turbulent structures associated with the primary RayleighTaylor instability.
 Authors:
 Graduate University for Advanced Studies (SOKENDAI), 3226 Oroshi, Toki, Gifu 5095292 (Japan)
 National Institute for Fusion Science, 3226 Oroshi, Toki, Gifu 5095292 (Japan)
 (SOKENDAI), 3226 Oroshi, Toki, Gifu 5095292 (Japan)
 Publication Date:
 OSTI Identifier:
 22423776
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 3; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; COMPUTERIZED SIMULATION; LARMOR RADIUS; MAGNETOHYDRODYNAMICS; NONLINEAR PROBLEMS; RAYLEIGHTAYLOR INSTABILITY; SLABS; TWODIMENSIONAL SYSTEMS
Citation Formats
Goto, R., Hatori, T., Miura, H., Email: miura.hideaki@nifs.ac.jp, Ito, A., Sato, M., and Graduate University for Advanced Studies. Formation of largescale structures with sharp density gradient through RayleighTaylor growth in a twodimensional slab under the twofluid and finite Larmor radius effects. United States: N. p., 2015.
Web. doi:10.1063/1.4916061.
Goto, R., Hatori, T., Miura, H., Email: miura.hideaki@nifs.ac.jp, Ito, A., Sato, M., & Graduate University for Advanced Studies. Formation of largescale structures with sharp density gradient through RayleighTaylor growth in a twodimensional slab under the twofluid and finite Larmor radius effects. United States. doi:10.1063/1.4916061.
Goto, R., Hatori, T., Miura, H., Email: miura.hideaki@nifs.ac.jp, Ito, A., Sato, M., and Graduate University for Advanced Studies. 2015.
"Formation of largescale structures with sharp density gradient through RayleighTaylor growth in a twodimensional slab under the twofluid and finite Larmor radius effects". United States.
doi:10.1063/1.4916061.
@article{osti_22423776,
title = {Formation of largescale structures with sharp density gradient through RayleighTaylor growth in a twodimensional slab under the twofluid and finite Larmor radius effects},
author = {Goto, R. and Hatori, T. and Miura, H., Email: miura.hideaki@nifs.ac.jp and Ito, A. and Sato, M. and Graduate University for Advanced Studies},
abstractNote = {Twofluid and the finite Larmor effects on linear and nonlinear growth of the RayleighTaylor instability in a twodimensional slab are studied numerically with special attention to highwavenumber dynamics and nonlinear structure formation at a low βvalue. The two effects stabilize the unstable high wave number modes for a certain range of the βvalue. In nonlinear simulations, the absence of the high wave number modes in the linear stage leads to the formation of the density field structure much larger than that in the singlefluid magnetohydrodynamic simulation, together with a sharp density gradient as well as a large velocity difference. The formation of the sharp velocity difference leads to a subsequent KelvinHelmholtztype instability only when both the twofluid and finite Larmor radius terms are incorporated, whereas it is not observed otherwise. It is shown that the emergence of the secondary instability can modify the outline of the turbulent structures associated with the primary RayleighTaylor instability.},
doi = {10.1063/1.4916061},
journal = {Physics of Plasmas},
number = 3,
volume = 22,
place = {United States},
year = 2015,
month = 3
}

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