# Dynamic equilibria and magnetohydrodynamic instabilities in toroidal plasmas with non-uniform transport coefficients

## Abstract

It can be shown that in the presence of a toroidal magnetic field induced by poloidal coils, combined with the electromagnetic field induced by a central solenoid, no static equilibrium is possible within the MHD description, as soon as non-zero resistivity is assumed. The resulting dynamic equilibrium was previously discussed for the case of spatially homogeneous resisitivity. In the present work, it is shown how a spatial inhomogeneity of the viscosity and resisitivity coefficients influences this equilibrium. Parameters in both the stable, tokamak-like regime and unstable, reversed field pinch-like regime are considered. It is shown that, whereas the magnitudes of the velocity and magnetic field fluctuations are strongly modified by the spatial variation of the transport coefficients, the qualitative flow behaviour remains largely unaffected.

- Authors:

- LMFA-CNRS UMR 5509, Ecole Centrale de Lyon, Université de Lyon, 69134 Ecully (France)
- CEA Cadarache, St. Paul Lez Durance (France)

- Publication Date:

- OSTI Identifier:
- 22410316

- Resource Type:
- Journal Article

- Journal Name:
- Physics of Plasmas

- Additional Journal Information:
- Journal Volume: 22; Journal Issue: 5; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1070-664X

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ELECTROMAGNETIC FIELDS; FLUCTUATIONS; MAGNETIC FIELDS; MAGNETOHYDRODYNAMICS; PLASMA; PLASMA INSTABILITY; REVERSED-FIELD PINCH DEVICES; REVERSE-FIELD PINCH; SOLENOIDS; TOKAMAK DEVICES; TOROIDAL CONFIGURATION; VISCOSITY

### Citation Formats

```
Futatani, Shimpei, Bos, Wouter J. T., and Morales, Jorge A.
```*Dynamic equilibria and magnetohydrodynamic instabilities in toroidal plasmas with non-uniform transport coefficients*. United States: N. p., 2015.
Web. doi:10.1063/1.4919960.

```
Futatani, Shimpei, Bos, Wouter J. T., & Morales, Jorge A.
```*Dynamic equilibria and magnetohydrodynamic instabilities in toroidal plasmas with non-uniform transport coefficients*. United States. doi:10.1063/1.4919960.

```
Futatani, Shimpei, Bos, Wouter J. T., and Morales, Jorge A. Fri .
"Dynamic equilibria and magnetohydrodynamic instabilities in toroidal plasmas with non-uniform transport coefficients". United States. doi:10.1063/1.4919960.
```

```
@article{osti_22410316,
```

title = {Dynamic equilibria and magnetohydrodynamic instabilities in toroidal plasmas with non-uniform transport coefficients},

author = {Futatani, Shimpei and Bos, Wouter J. T. and Morales, Jorge A.},

abstractNote = {It can be shown that in the presence of a toroidal magnetic field induced by poloidal coils, combined with the electromagnetic field induced by a central solenoid, no static equilibrium is possible within the MHD description, as soon as non-zero resistivity is assumed. The resulting dynamic equilibrium was previously discussed for the case of spatially homogeneous resisitivity. In the present work, it is shown how a spatial inhomogeneity of the viscosity and resisitivity coefficients influences this equilibrium. Parameters in both the stable, tokamak-like regime and unstable, reversed field pinch-like regime are considered. It is shown that, whereas the magnitudes of the velocity and magnetic field fluctuations are strongly modified by the spatial variation of the transport coefficients, the qualitative flow behaviour remains largely unaffected.},

doi = {10.1063/1.4919960},

journal = {Physics of Plasmas},

issn = {1070-664X},

number = 5,

volume = 22,

place = {United States},

year = {2015},

month = {5}

}