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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
Meeting Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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WIPP’s SSCVS: A breath of fresh air
This spring, the Department of Energy’s Office of Environmental Management announced that it had achieved a major milestone by completing commissioning of the Safety Significant Confinement Ventilation System (SSCVS) facility—a new, state-of-the-art, large-scale ventilation system at the Waste Isolation Pilot Plant, the DOE’s geologic repository for defense-related transuranic (TRU) waste in New Mexico.
Raymond J. Juzaitis
Nuclear Science and Engineering | Volume 80 | Number 3 | March 1982 | Pages 424-447
Technical Paper | doi.org/10.13182/NSE82-A19829
Articles are hosted by Taylor and Francis Online.
A deterministic analysis of the computational cost associated with geometric splitting/Russian roulette in Monte Carlo radiation transport calculations is presented. Appropriate integro-differential equations (based on the theory of Monte Carlo errors) are developed for the first and second moments of the tally as well as for the expected value of time per particle history, given that splitting with Russian roulette takes place at one or more internal surfaces of the geometry. The equations are solved using a standard Sn solution technique, allowing for the prediction of computer cost (formulated as the product of sample variance and time per particle history) associated with a given set of splitting parameters. Extensive numerical results relating to the transport model chosen for study (namely, particle transmission through a semi-infinite slab shield composed of an isotropically scattering medium) are presented. Optimum splitting surface locations and splitting ratios are determined. Single-surface results indicate that the threshold slab thickness for which any splitting becomes cost effective varies from ∼2 to >7 mean-free-paths, depending on the degree of scattering in the medium. When splitting is cost effective, it is so over a wide range of surface locations. Benefits of such an analysis are particularly noteworthy for transport problems in which splitting is apt to be extensively employed (e.g., deep-penetration calculations).