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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Chris Wagner: The role of Eden Radioisotopes in the future of nuclear medicine
Chris Wagner has more than 40 years of experience in nuclear medicine, beginning as a clinical practitioner before moving into leadership roles at companies like Mallinckrodt (now Curium) and Nordion. His knowledge of both the clinical and the manufacturing sides of nuclear medicine laid the groundwork for helping to found Eden Radioisotopes, a start-up venture that intends to make diagnostic and therapeutic raw material medical isotopes like molybdenum-99 and lutetium-177.
S. Y. Jiang, X. X. Wu, Y. J. Zhang
Nuclear Science and Engineering | Volume 135 | Number 2 | June 2000 | Pages 177-189
Technical Paper | doi.org/10.13182/NSE00-A2133
Articles are hosted by Taylor and Francis Online.
The experiment was performed on the test loop HRTL-5, which simulates the geometry and system design of the 5-MW nuclear heating reactor developed by the Institute of Nuclear Energy Technology, Tsinghua University. The flow behavior for a wide range of inlet subcoolings, in which the flow experience varies from single- to two-phase, is described in a natural circulation system at different pressures (p = 0.1, 0.24, and 1.5 MPa). Several kinds of flow instability are investigated, including geysering, flashing-related flow instability, and high-frequency flow oscillation at p = 0.1 and 0.24 MPa, as well as low steam quality density wave oscillation at p = 1.5 MPa. The mechanisms of geysering, which has new features, and flashing-related flow instability, which has never been studied well enough in this field, are particularly interpreted. The experimental results show the following: First, for a low-pressure natural circulation system, the two-phase flow is unstable in most inlet subcooling conditions, and the two-phase stable flow can be reached only with very low inlet subcoolings. Second, at high inlet subcoolings, the flow instability is dominated by subcooling boiling in the heated section, and at intermediate inlet subcoolings, it is dominated by void flashing in the adiabatic long riser. Third, in the two-phase stable flow region, the conditions for boiling out of the core, namely, single-phase flow in the heated section and two-phase flow in the riser due to vapor flashing, can be realized. The experimental results are of significance for the design and accident analysis of vessel and swimming pool-type natural circulation nuclear heating reactors.