Simulated Material Erosion from Plasma Facing Components in Tokomak Reactors

dc.contributor.authorEchols, John Russellen
dc.contributor.committeechairWinfrey, Leighen
dc.contributor.committeememberReynolds, William T. Jr.en
dc.contributor.committeememberHin, Celineen
dc.contributor.departmentMaterials Science and Engineeringen
dc.date.accessioned2015-02-05T09:00:31Zen
dc.date.available2015-02-05T09:00:31Zen
dc.date.issued2015-02-04en
dc.description.abstractMaterial erosion, melting, splashing, bubbling, and ejection during disruption events in future large tokamak reactors are of serious concern to component longevity. The majority of the heat flux during disruptions will be incident on the divertor, which will be made from tungsten in the future large tokamak ITER. Electrothermal plasma sources operating in the confined controlled arc discharge regime produce heat fluxes in the range expected for hard disruptions in future large tokamaks. The radiative heat flux produced inside of the capillary discharge channel is from the formed high density (10^23 - 10^27/m^3) plasma with heat fluxes of up to 125 GW/m^2 over a period of 100s of microseconds, making such sources excellent simulators for ablation studies of plasma-facing materials in tokamaks during hard disruptions. Experiments have been carried out with the PIPE device exposing tungsten to these high heat flux plasmas. SEM images have been taken of the tungsten surfaces, cross sections of tungsten surfaces, and ejected material. Melting and bubble/void formation has been observed on the tungsten surface. The tungsten surface shows evidence of melt-layer flow and the existence of voids and cracks in the exposed material. The ejected material does not show direct evidence of liquid material ejection which would lead to splashing. EDS analysis has been performed on the ejected material which demonstrates a lack of deposited solid tungsten particulates greater than micron size.en
dc.description.degreeMaster of Scienceen
dc.format.mediumETDen
dc.identifier.othervt_gsexam:4256en
dc.identifier.urihttp://hdl.handle.net/10919/51261en
dc.publisherVirginia Techen
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subjectTungstenen
dc.subjectFusion Materialsen
dc.subjectHigh Heat Fluxen
dc.subjectPlasma Facing Componentsen
dc.subjectPlasma Facing Materialsen
dc.titleSimulated Material Erosion from Plasma Facing Components in Tokomak Reactorsen
dc.typeThesisen
thesis.degree.disciplineMaterials Science and Engineeringen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.levelmastersen
thesis.degree.nameMaster of Scienceen

Files

Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
Echols_JR_T_2015.pdf
Size:
7.98 MB
Format:
Adobe Portable Document Format

Collections