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Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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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Latest News
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.
Amir N. Nahavandi
Nuclear Science and Engineering | Volume 36 | Number 2 | May 1969 | Pages 159-188
Technical Paper | doi.org/10.13182/NSE69-A19715
Articles are hosted by Taylor and Francis Online.
A generalized digital computer approach to analyze the loss-of-coolant accident in pressurized water reactors requires a systematic specification of the plant geometric, physical, and topological characteristics and initial conditions. The solution of the problem is hampered by numerical stability and convergence problems which can be remedied by first classifying the problem variables into three categories: 1) numerically-integrated; 2) analytically-integrated; and 3) auxiliary algebraic variables. Second, in view of the occurrence of the acoustic wave phenomenon, the maximum allowable integration time step should be kept much smaller than the subharmonics present in the solution. Another distinctive feature of this study is the treatment of stratified elements, such as the pressurizer or the steam generator secondary. Allowance for mass exchange between the top and bottom control volumes in these elements is made by the introduction of bubble rise and condensate drop velocity concepts. Furthermore, to eliminate unrealistic pressure fluctuations in the ruptured elements at the onset of two-phase blowdown, critical flow models including inertia effects are introduced. To verify the sensitivity of the solution to various two-phase frictional loss correlations, five well-known correlations are reviewed. A comparison of the analytical results against LOFT experimental data demonstrates a good agreement and shows that a more accurate prediction would require the introduction of metastability analysis.