Numerical simulation of water-cooled sample holders for high-heat flux testing of low-level irradiated materials

Charry León, Carlos Humberto

Title:

Numerical simulation of water-cooled sample holders for high-heat flux testing of low-level irradiated materials

dc.contributor.advisor	Yoda, Minami
dc.contributor.advisor	Abdel-Khalik, Said I.
dc.contributor.author	Charry León, Carlos Humberto
dc.contributor.committeeMember	Ghiaasiaan, S. Mostafa
dc.contributor.department	Mechanical Engineering
dc.date.accessioned	2015-01-12T20:53:20Z
dc.date.available	2015-01-12T20:53:20Z
dc.date.created	2014-12
dc.date.issued	2014-12-04
dc.date.submitted	December 2014
dc.date.updated	2015-01-12T20:53:20Z
dc.description.abstract	The promise of a vast source of energy to power the world and protect our planet using fusion technology has been the driving force for scientists and engineers around the globe for more than sixty years. Although the materialization of this ideal still in the distance, multiple scientific and technological advances have been accomplished, which have brought commercial fusion power closer to a reality than it has ever been. As part of the collaborative effort in the pursuit of realizable fusion energy, the International Thermonuclear Experimental Reactor (ITER) is being developed by a coalition of nations of which the United States is a part of. One critical technological challenge for ITER is the development of adequate plasma facing materials (PFMs) that can withstand the strenuous conditions of operation. To date, high heat flux (HHF) testing has been conducted mainly on non-irradiated specimens due to the difficulty of working with radioactive specimens, such as instrument contamination. In this thesis, the new Irradiated Material Target Station (IMTS) facility for fusion materials at Oak Ridge National Laboratory (ORNL), in which the HHFs are provided by water-wall plasma-arc lamps (PALs), is considered for neutron-irradiated specimens, especially tungsten. The facility is being used to test irradiated plasma-facing components materials for magnetic fusion reactors as part of the US-Japan plasma facing components evaluation by tritium plasma, heat and neutron irradiation experiments (PHENIX). In order to conduct HHF testing on the PFMs various sample holders designs were developed to accommodate radioactive specimens during HHF testing. As part of the effort to design sample holders that are compatible with the IMTS facility, numerical simulations were performed for different water-cooled sample holder designs with the commercial computational fluid dynamics (CFD) software package, ANSYS™ FLUENT®. The numerical models are validated against experimental temperature measurements obtained from the IMTS facility. These experimentally validated numerical models are used to assess the thermal performance of two sample holder designs and establish safe limits for HHF testing under various operating conditions. The limiting parameter for the current configuration was determined for each sample holder design. For the Gen 1 sample holder, the maximum temperature reached within the Copper rod limits the allowable incident heat flux to about 6 MW/m². In the case of the Gen 2 sample holder, the maximum temperature reached within the Molybdenum clamping disk limits the allowable incident heat flux to about 5 MW/m². In addition, the numerical model are used to parametrically investigate the effect of the operating pressure, mass flow rate, and incident heat flux on the local heat flux distributions and peak surface temperatures. Finally, a comparative analysis is conducted to evaluate the advantages and disadvantages associated with the main design modifications between the two sample holder models as to evaluate their impact in the overall thermal performance of each sample holder in order to provide conclusive recommendations for future sample holder designs.
dc.description.degree	M.S.
dc.format.mimetype	application/pdf
dc.identifier.uri	http://hdl.handle.net/1853/53100
dc.language.iso	en_US
dc.publisher	Georgia Institute of Technology
dc.subject	Plasma facing materials
dc.subject	Fusion energy
dc.subject	IMTS facility
dc.subject	Sample holders
dc.subject	Irradiated samples
dc.subject	Fusion technology
dc.subject	ITER
dc.title	Numerical simulation of water-cooled sample holders for high-heat flux testing of low-level irradiated materials
dc.type	Text
dc.type.genre	Thesis
dspace.entity.type	Publication
local.contributor.advisor	Abdel-Khalik, Said I.
local.contributor.advisor	Yoda, Minami
local.contributor.corporatename	George W. Woodruff School of Mechanical Engineering
local.contributor.corporatename	College of Engineering
relation.isAdvisorOfPublication	196f5fb4-8c6b-4b41-add5-06b1d33b971c
relation.isAdvisorOfPublication	d318e6bc-95be-4fd2-bb0a-19fe480686df
relation.isOrgUnitOfPublication	c01ff908-c25f-439b-bf10-a074ed886bb7
relation.isOrgUnitOfPublication	7c022d60-21d5-497c-b552-95e489a06569
thesis.degree.level	Masters