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The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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Proving DRACO will deliver
The United States is now closer than it has been in over five decades to launching the first nuclear thermal rocket into space, thanks to DRACO—the Demonstration Rocket for Agile Cislunar Orbit.
Robert Zboray, Wilhelmus J. M. de Kruijf, Tim H. J. J. van der Hagen, Hugo van Dam
Nuclear Technology | Volume 136 | Number 3 | December 2001 | Pages 301-314
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT01-A3247
Articles are hosted by Taylor and Francis Online.
Linear stability analysis of a natural-circulation boiling water reactor (BWR) and the underlying thermal-hydraulic subsystem is performed using a reduced-order BWR dynamic model. The root-locus method is used to examine the stability of the system. The relation between the poles of the system and the physical processes causing the instabilities is investigated. For a natural-circulation thermal-hydraulic system, the two types of instabilities (type-I and type-II oscillations) can clearly be attributed to the dynamics of different types of pressure drops. However, it is not possible to associate these instability types with certain poles of the system.The root loci of a reactor with weak void reactivity feedback and those of the thermal-hydraulic system behave similarly: The same pole pair remains the least stable one as the operating conditions move from the type-I instability region to the type-II region. In the case of a reactor with strong void reactivity feedback, an exchange in the stability of two pole pairs is found: The least stable pole pair in the type-II region is not the same as in the type-I region.