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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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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Latest News
Dragonfly, a Pu-fueled drone heading to Titan, gets key NASA approval
Curiosity landed on Mars sporting a radioisotope thermoelectric generator (RTG) in 2012, and a second NASA rover, Perseverance, landed in 2021. Both are still rolling across the red planet in the name of science. Another exploratory craft with a similar plutonium-238–fueled RTG but a very different mission—to fly between multiple test sites on Titan, Saturn’s largest moon—recently got one step closer to deployment.
On April 25, NASA and the Johns Hopkins University Applied Physics Laboratory (APL) announced that the Dragonfly mission to Saturn’s icy moon passed its critical design review. “Passing this mission milestone means that Dragonfly’s mission design, fabrication, integration, and test plans are all approved, and the mission can now turn its attention to the construction of the spacecraft itself,” according to NASA.
Keni Zhang, Jean Croisé, Gerhard Mayer
Nuclear Technology | Volume 174 | Number 3 | June 2011 | Pages 364-374
Technical Paper | TOUGH2 Symposium / Radioactive Waste Management and Disposal | doi.org/10.13182/NT11-A11746
Articles are hosted by Taylor and Francis Online.
Significant quantities of hydrogen can be produced by the corrosion of metal components. It is necessary to forecast gas migration and pressure buildup in the context of deep geological radioactive waste disposal. One of the major problems in representing gas migration in a radioactive waste repository is that of simultaneously modeling all gas sources and complex transfer pathways constituted by the network of underground drifts and the surrounding low-permeability rock. In 2006, the French National Agency for Radioactive Waste Management launched an international multiphase flow simulation benchmark exercise for modeling such a two-phase (gas and liquid) flow system. The exercise was designed to compare the performance of the numerical methods being used to resolve the designed problems. This paper presents the results of test case 2 of the exercise completed by the authors. The three-dimensional model represents a fraction of a repository for long-lived radioactive waste in a clay rock. The model simulates ambient pressure and flow conditions (considering influence of site evacuation on the flow system) after placement of wastes, with full consideration of two-phase initial and boundary conditions. Isothermal conditions are assumed. Time-dependent gas sources are applied to the model. Since the natural environment is unable to evacuate the entire amount of hydrogen in a dissolved state, a free gas phase is formed within the disposal structures. The model is used to study the dissipation of those gases to determine their influence on the transient phases throughout the lifetime of the repository, and to investigate possible pressure buildup, which may introduce a risk of damage to the host rock. We use the model to investigate how the presence of gas in the repository influences the nature of water flow around the disposal structures and the resaturation (process of saturation increasing) transient processes after closure of the repository. The TOUGH2-MP code, a parallel multiphase flow simulator, has been adopted for this study.
