# Remapping HELENA to incompressible plasma rotation parallel to the magnetic field

## Abstract

Plasma rotation in connection to both zonal and mean (equilibrium) flows can play a role in the transitions to the advanced confinement regimes in tokamaks, as the L-H transition and the formation of internal transport barriers (ITBs). For incompressible rotation, the equilibrium is governed by a generalised Grad-Shafranov (GGS) equation and a decoupled Bernoulli-type equation for the pressure. For parallel flow, the GGS equation can be transformed to one identical in form with the usual Grad-Shafranov equation. In the present study on the basis of the latter equation, we have extended HELENA, an equilibrium fixed boundary solver. The extended code solves the GGS equation for a variety of the two free-surface-function terms involved for arbitrary Alfvén Mach number and density functions. We have constructed diverted-boundary equilibria pertinent to ITER and examined their characteristics, in particular, as concerns the impact of rotation on certain equilibrium quantities. It turns out that the rotation and its shear affect noticeably the pressure and toroidal current density with the impact on the current density being stronger in the parallel direction than in the toroidal one.

- Authors:

- Physics Department, University of Ioannina, Ioannina 451 10 (Greece)
- Max-Planck Institut für Plasma Physics, 85748 Garching bei München (Germany)

- Publication Date:

- OSTI Identifier:
- 22599997

- Resource Type:
- Journal Article

- Resource Relation:
- Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 7; Other Information: (c) 2016 EURATOM; Country of input: International Atomic Energy Agency (IAEA)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CHARGED-PARTICLE TRANSPORT; CURRENT DENSITY; EQUILIBRIUM; GRAD-SHAFRANOV EQUATION; ITER TOKAMAK; MACH NUMBER; MAGNETIC FIELDS; PLASMA; PLASMA CONFINEMENT; ROTATING PLASMA; TRANSPORT THEORY

### Citation Formats

```
Poulipoulis, G., Throumoulopoulos, G. N., and Konz, C.
```*Remapping HELENA to incompressible plasma rotation parallel to the magnetic field*. United States: N. p., 2016.
Web. doi:10.1063/1.4955326.

```
Poulipoulis, G., Throumoulopoulos, G. N., & Konz, C.
```*Remapping HELENA to incompressible plasma rotation parallel to the magnetic field*. United States. doi:10.1063/1.4955326.

```
Poulipoulis, G., Throumoulopoulos, G. N., and Konz, C. Fri .
"Remapping HELENA to incompressible plasma rotation parallel to the magnetic field". United States.
doi:10.1063/1.4955326.
```

```
@article{osti_22599997,
```

title = {Remapping HELENA to incompressible plasma rotation parallel to the magnetic field},

author = {Poulipoulis, G. and Throumoulopoulos, G. N. and Konz, C.},

abstractNote = {Plasma rotation in connection to both zonal and mean (equilibrium) flows can play a role in the transitions to the advanced confinement regimes in tokamaks, as the L-H transition and the formation of internal transport barriers (ITBs). For incompressible rotation, the equilibrium is governed by a generalised Grad-Shafranov (GGS) equation and a decoupled Bernoulli-type equation for the pressure. For parallel flow, the GGS equation can be transformed to one identical in form with the usual Grad-Shafranov equation. In the present study on the basis of the latter equation, we have extended HELENA, an equilibrium fixed boundary solver. The extended code solves the GGS equation for a variety of the two free-surface-function terms involved for arbitrary Alfvén Mach number and density functions. We have constructed diverted-boundary equilibria pertinent to ITER and examined their characteristics, in particular, as concerns the impact of rotation on certain equilibrium quantities. It turns out that the rotation and its shear affect noticeably the pressure and toroidal current density with the impact on the current density being stronger in the parallel direction than in the toroidal one.},

doi = {10.1063/1.4955326},

journal = {Physics of Plasmas},

number = 7,

volume = 23,

place = {United States},

year = {Fri Jul 15 00:00:00 EDT 2016},

month = {Fri Jul 15 00:00:00 EDT 2016}

}