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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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ANS and the U.K.’s NI announce reciprocal membership agreement
With President Trump on a state visit to the U.K., in part to sign a landmark new agreement on U.S.-U.K. nuclear collaboration, a flurry of transatlantic partnerships and deals bridging the countries’ nuclear sectors have been announced.
The American Nuclear Society is taking an active role in this bridge-building by forming a reciprocal membership agreement with the U.K.’s Nuclear Institute.
Jae Jun Jeong, Dae Hyun Hwang, Bub Dong Chung
Nuclear Technology | Volume 156 | Number 3 | December 2006 | Pages 360-368
Technical Note | Thermal Hydraulics | doi.org/10.13182/NT06-A3797
Articles are hosted by Taylor and Francis Online.
MARS is a best-estimate system analysis code that is based on the RELAP5/MOD3 and COBRA-TF codes. The COBRA-TF code was adapted as a three-dimensional thermal-hydraulic module in MARS. It uses a two-fluid, three-field model for two-phase flows and has a subchannel flow mixing model. The subchannel flow mixing model of the MARS three-dimensional module was assessed by using the ISPRA 16-rod bundle test and the GE 9-rod bundle test data. These tests represent typical pressurized water reactor and boiling water reactor core thermal-hydraulic conditions, respectively. Two interconnected subchannel tests that were performed under atmospheric pressure conditions were also used for the assessment. From the results of the assessments, a simple modification of the subchannel flow mixing model was suggested to take into account the effects of the system pressure on the void drift phenomena.
