ParameterSpace Survey of Linear Gmode and Interchange in Extended Magnetohydrodynamics
The extended magnetohydrodynamic stability of interchange modes is studied in two configurations. In slab geometry, a local dispersion relation for the gravitational interchange mode (gmode) with three different extensions of the MHD model [P. Zhu, et al., Phys. Rev. Lett. 101, 085005 (2008)] is analyzed. Our results delineate where drifts stablize the gmode with gyroviscosity alone and with a twofluid Ohm’s law alone. Including the twofluid Ohm’s law produces an ion drift wave that interacts with the gmode. This interaction then gives rise to a second instability at finite k _{y}. A second instability is also observed in numerical extended MHD computations of linear interchange in cylindrical screwpinch equilibria, the second configuration. Particularly with incomplete models, this mode limits the regions of stability for physically realistic conditions. But, applying a consistent twotemperature extended MHD model that includes the diamagnetic heat flux density ($$\vec{q}$$ _{*}) makes the onset of the second mode occur at larger Hall parameter. For conditions relevant to the SSPX experiment [E.B. Hooper, Plasma Phys. Controlled Fusion 54, 113001 (2012)], significant stabilization is observed for Suydam parameters as large as unity (D _{s}≲1).
 Authors:

^{[1]};
^{[1]}
 Univ. of Wisconsin, Madison, WI (United States). Dept. of Engineering Physics
 Publication Date:
 Report Number(s):
 UWCPTC 175
Journal ID: ISSN 1070664X
 Grant/Contract Number:
 FG0206ER54850; FC0205ER54813; FC0208ER54975
 Type:
 Accepted Manuscript
 Journal Name:
 Physics of Plasmas
 Additional Journal Information:
 Journal Volume: 24; Journal Issue: 10; Journal ID: ISSN 1070664X
 Publisher:
 American Institute of Physics (AIP)
 Research Org:
 Univ. of Wisconsin, Madison, WI (United States)
 Sponsoring Org:
 USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC24)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; mathematical foundations: fluid and multifluid theory; instabilities: hydromagnetic; computer simulation: MHD
 OSTI Identifier:
 1390175
 Alternate Identifier(s):
 OSTI ID: 1395917; OSTI ID: 1436977
Howell, E. C., and Sovinec, C. R.. ParameterSpace Survey of Linear Gmode and Interchange in Extended Magnetohydrodynamics. United States: N. p.,
Web. doi:10.1063/1.4993440.
Howell, E. C., & Sovinec, C. R.. ParameterSpace Survey of Linear Gmode and Interchange in Extended Magnetohydrodynamics. United States. doi:10.1063/1.4993440.
Howell, E. C., and Sovinec, C. R.. 2017.
"ParameterSpace Survey of Linear Gmode and Interchange in Extended Magnetohydrodynamics". United States.
doi:10.1063/1.4993440. https://www.osti.gov/servlets/purl/1390175.
@article{osti_1390175,
title = {ParameterSpace Survey of Linear Gmode and Interchange in Extended Magnetohydrodynamics},
author = {Howell, E. C. and Sovinec, C. R.},
abstractNote = {The extended magnetohydrodynamic stability of interchange modes is studied in two configurations. In slab geometry, a local dispersion relation for the gravitational interchange mode (gmode) with three different extensions of the MHD model [P. Zhu, et al., Phys. Rev. Lett. 101, 085005 (2008)] is analyzed. Our results delineate where drifts stablize the gmode with gyroviscosity alone and with a twofluid Ohm’s law alone. Including the twofluid Ohm’s law produces an ion drift wave that interacts with the gmode. This interaction then gives rise to a second instability at finite ky. A second instability is also observed in numerical extended MHD computations of linear interchange in cylindrical screwpinch equilibria, the second configuration. Particularly with incomplete models, this mode limits the regions of stability for physically realistic conditions. But, applying a consistent twotemperature extended MHD model that includes the diamagnetic heat flux density ($\vec{q}$*) makes the onset of the second mode occur at larger Hall parameter. For conditions relevant to the SSPX experiment [E.B. Hooper, Plasma Phys. Controlled Fusion 54, 113001 (2012)], significant stabilization is observed for Suydam parameters as large as unity (Ds≲1).},
doi = {10.1063/1.4993440},
journal = {Physics of Plasmas},
number = 10,
volume = 24,
place = {United States},
year = {2017},
month = {9}
}