Graduate Thesis Or Dissertation


A thermal hydraulics analysis of a molybdenum production element for implementation in TRIGA reactors Public Deposited

Downloadable Content

Download PDF


Attribute NameValues
  • The metastable isotope of technetium-99 (Tc-99m) is an important diagnostic tool used in the field of nuclear medicine due to the isotope's 6.0 hour half-life, 140.5 keV γ-decay mechanism, and multiple oxidation states [1,2]. Approximately 70% of the world’s nuclear medicine procedures involve the use of Tc-99m [3]. The conventional source of Tc-99m comes from the β-decay of molybdenum-99 (Mo-99), an isotope which may be produced via the fission of uranium-235 (U-235) atoms [2]. As Mo-99 has a half-life of 2.7 hours [2]; it is difficult to produce anything but short-term stockpiles of Tc-99m. A handful of geographically dispersed facilities maintain a continuous production of Mo-99 via U-235 fission as a means to satisfy the demand of nuclear medicine worldwide [4]. However, 96% of all Mo-99 production is concentrated among only 4 facilities [4]. This centralized production dynamic has been shown to leave the world susceptible to Tc-99m shortages in the event of multiple reactor shutdowns [5]. Oregon State University (OSU) has undertaken a study to investigate the safety of implementing a fueled experiment, known as the molybdenum element, within the OSU TRIGA® reactor (OSTR) for the purpose of producing Mo-99. This study investigates both steady-state and select transient conditions within the OSTR core with the use of the lumped parameter code RELAP5-3D version 2.4.2. Key thermal hydraulic parameters which may impact the safety of the OSTR are identified and presented, and discussed herein.
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Committee Member
Academic Affiliation
Non-Academic Affiliation
Rights Statement
Peer Reviewed



This work has no parents.

In Collection: