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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Industry Update—May 2025
Here is a recap of industry happenings from the recent past:
TerraPower’s Natrium reactor advances on several fronts
TerraPower has continued making aggressive progress in several areas for its under-construction Natrium Reactor Demonstration Project since the beginning of the year. Natrium is an advanced 345-MWe reactor that has liquid sodium as a coolant, improved fuel utilization, enhanced safety features, and an integrated energy storage system, allowing for a brief power output boost to 500-MWe if needed for grid resiliency. The company broke ground for its first Natrium plant in 2024 near a retiring coal plant in Kemmerer, Wyo.
Joseph O. Erb, James G. Miller
Nuclear Technology | Volume 83 | Number 3 | December 1988 | Pages 367-373
Technical Paper | Fifth International Retran Meeting / Heat Transfer and Fluid Flow | doi.org/10.13182/NT88-A34149
Articles are hosted by Taylor and Francis Online.
The rod ejection transient is a postulated Condition IV event initiated by the mechanical failure of a control rod mechanism pressure housing. Such a failure results in the rapid ejection of a rod cluster control assembly from the core, followed by a fast reactivity insertion. A severe asymmetric core power distribution may result, possibly leading to fuel rod damage. Reactor protection for the transient is provided by negative reactivity feedback effects and by reactor trips on high neutron flux levels. This transient has been modeled for Virginia Electric and Power Company’s Surry and North Anna nuclear power stations using RETRAN-02. The analysis is performed in two parts. First, the core average power history is calculated using a single-loop model with point kinetics and three axially stacked core control volumes. The ejected rod’s reactivity is inserted linearly over 0.1 s. The negative reactivity feedback effects due to Doppler and moderator temperature changes and the reactor trip are also modeled. The effect of the locally peaked core flux shape, omitted by the nominal point kinetics model, is approximated by applying a conservative power weighting factor to the Doppler reactivity feedback. The core average power history is adjusted to represent peak core power conditions and input to the hot spot thermal-hydraulic analysis model. The hot spot model, which represents a single fuel rod at the core’s peak power, predicts maximum fuel enthalpy and temperature transients. This model has two control volumes, one for the hot spot location and the second for a sink for flow from the hot channel. From these results, the amount of fuel damage and the radiological consequences can be assessed.