Finite element simulation for validation of multi-dipole line cusp magnetic field configuration for MPD

TL;DR

This paper uses finite element simulation to validate the magnetic field configuration of a multi-dipole line cusp plasma device, demonstrating good agreement with experimental measurements and control over the null region.

Contribution

It presents the first 3-D finite element simulation of the multi-dipole line cusp magnetic field in a large chamber, validating experimental results and showing control over magnetic field profiles.

Findings

Simulation results agree with experimental magnetic field profiles.

The configuration allows control over the null region and magnetic field variation.

Magnetic field profiles over the device's end cross-section are characterized.

Abstract

A Multi-dipole line cusp configured Plasma Device (MPD) having six electromagnets with embedded Vacoflux-50 as a core material has been operated with a capability to experimentally control the field-free region, the radial profile of magnetic field, and pole magnetic field by changing magnet current. For the validation of multi-dipole line cusp magnetic field (MMF) configuration in a 3-D geometry, a finite element simulation has been performed using COMSOL software. This paper presents 3-D magnetic field simulation results of multi-pole line cusp magnetic field configuration performed over the 1.2m length and 40cm diameter chamber in the vacuum condition. The simulation results show good agreement with the experimentally measured magnetic field profile. The performed magnetic field simulation results clearly capture that this configuration has full control over a null region (nearly field-free region) as well is capable to change the magnetic field values and radial variation of the magnetic field. Moreover, the magnetic field profiles over the end cross-section of the device have been discussed.