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NRC proposed rule for licensing reactors authorized by DOE, DOD
Nuclear reactor designs approved by the Department of Energy or Department of Defense could get streamlined pathways through the Nuclear Regulatory Commission’s commercial licensing process should applicants wish to push the technology into the civilian sector.
A proposed rule introduced April 2 by the NRC would “improve NRC licensing review efficiency, where applicable, by explicitly establishing by regulation an additional means for reactor applicants to demonstrate the safety functions of their reactor designs, and thus, would contribute to the safe and secure use and deployment of civilian nuclear energy technologies.”
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.
