Thermal Design of Wide Beam Area X-Ray Sources

digital mammography;CFD;diffraction enhanced imaging;wide x-ray source;thermal design

Bobolea, Nicolae Alin ; J. Michael Doster, Committee Chair,K. Linga Murty, Committee Member,Mohamed A. Bourham, Committee Member,Bobolea, Nicolae Alin ; J. Michael Doster ; Committee Chair ; K. Linga Murty ; Committee Member ; Mohamed A. Bourham ; Committee Member

University:North Carolina State University

关键词: digital mammography;    CFD;    diffraction enhanced imaging;    wide x-ray source;    thermal design;   

Others  :  https://repository.lib.ncsu.edu/bitstream/handle/1840.16/726/etd.pdf?sequence=1&isAllowed=y

美国|英语

来源: null

【 摘 要 】

Diffraction Enhanced Imaging (DEI) with x-ray radiation provided by a synchrotron source has been shown to provide good image contrast at lower radiation dose for materials with small x-ray attenuation coefficient As a result, DEI has received significant interest for digital mammography and other medical imaging applications. However, deployment of a synchrotron source at a medical facility is not currently feasible due to its size and costs. Consequently, a compact x-ray source capable of delivering x-ray intensities and beam collimation similar to a synchrotron accelerator is desirable. A wide beam area x-ray source has been suggested as a possible alternative to a synchrotron source, with the x-rays generated by electron bombardment of a suitable target material. Previous research work demonstrated a prototype scale cylindrical shaped oxygen free copper target with a layer of molybdenum to be feasible from an engineering perspective. An industrial size DEI facility requires a scale-up of the proof-of-principle design. The x-ray flux necessary for high image quality implies significant heat loading on the x-ray source.Safe operation of a full scale DEI facility is reliant upon a thermal management solution capable of rejecting this heat. An active target cooling system has been proposed and its performance has been evaluated through CFD simulation. The design ensures the maximum target temperature is maintained at reasonable levels and coolant boiling is not reached under the most demanding operating conditions.