Design and Characterization of a Dust Injector for Future Studies of Tungsten Dust in the STOR-M Plasma
Date
2021-01-09
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
ORCID
Type
Thesis
Degree Level
Masters
Abstract
Dust generation from Plasma Facing Components (PFC) is a problem for tokamaks as they
approach suitable reactor conditions. Tungsten dust is especially detrimental in the core,
due to associated high Z bremsstrahlung power losses. As Tungsten is a primary candidate
for PFC materials in large projects such as ITER, this remains a pressing issue. In order
to better understand dust dynamics in tokamaks, a dust injection experiment is proposed
for the Saskatchewan Torus-Modified (STOR-M). This experiment will utilize calibrated,
spherical tungsten micro-particles. A known mass of these tungsten micro-particles are
to be injected into STOR-M with control over the position of the dust plume. This will
enable future observation and study of dust dynamics within STOR-M.
In preparation for this experiment, a new dust injector has been designed, based on the
fast gas valve for the University of Saskatchewan Compact Torus Injector. An experimental
test apparatus was developed to characterize the dust injector. In the experiment, nitrogen
gas and dust particles are injected into the test vacuum chamber under various dust
injector parameters. Vacuum chamber pressures range from 10−4
- 10−5 Torr, which is
within the operation range of STOR-M. These particles are then imaged with a high-speed
camera via laser light scattering. Collected 12-bit raw image data was then processed and
analysed. This analysis fully characterizes the dust injector in terms of the time evolution
of the injector dust plume, amount of gas injected and injected dust mass.
Description
Keywords
Dust Injector, Tokamak, Compact Torus, Tungsten Dust
Citation
Degree
Master of Science (M.Sc.)
Department
Physics and Engineering Physics
Program
Physics